diff --git a/apps/as/src/entities/instl-sncn/index.ts b/apps/as/src/entities/instl-sncn/index.ts
index 875a1e162..9547dd6db 100644
--- a/apps/as/src/entities/instl-sncn/index.ts
+++ b/apps/as/src/entities/instl-sncn/index.ts
@@ -5,6 +5,7 @@ export {
   useInstlSncnList,
   useInstlSncnSidoCombo,
   useInstlSncnSigunguCombo,
+  useInstlSncnTechReview,
 } from "./api/queries";
 export {
   type AdstZoneResponseDto,
@@ -26,5 +27,7 @@ export {
   type InstlSncnMngSaveRequestDto,
   type InstlSncnMngSearchParams,
   type InstlSncnRvwOpnnResponseDto,
+  type InstlSncnRvwOpnnSaveRequestDto,
+  type InstlSncnSplmntDmndSaveDto,
   type ReviewStepCode,
 } from "./model/instl-sncn-interface";
diff --git a/apps/as/src/entities/instl-sncn/model/instl-sncn-interface.ts b/apps/as/src/entities/instl-sncn/model/instl-sncn-interface.ts
index c8ab5e56f..378d1e427 100644
--- a/apps/as/src/entities/instl-sncn/model/instl-sncn-interface.ts
+++ b/apps/as/src/entities/instl-sncn/model/instl-sncn-interface.ts
@@ -114,14 +114,14 @@ export interface InstlSncnMngResponseDto extends InstlSncnMngSaveRequestDto {
 export interface InstlSncnBzScaleSaveDto {
   /** 공종구분코드 */
   cnstpSeCd: string;
-  /** 기본계획(A) */
+  /** 기본계획수량 */
   bscPl: number;
-  /** 예산반영(B) */
+  /** 예산반영수량 */
   budgetReflct: number;
-  /** 금회설계시(C) */
+  /** 금회설계수량 */
   thtiDsgn: number;
-  /** 증감(C-B) */
-  diff: number;
+  /** 증감(C-B) — 클라이언트 계산용, API 미전송 */
+  diff?: number;
 }
 
 /** 설치인가 신청 - 총사업비 저장 DTO(배열 원소) */
@@ -138,27 +138,92 @@ export interface InstlSncnBizCstSaveRequestDto {
 
 /** 설치인가 신청 - 체크리스트 결과 저장 DTO(배열 원소) */
 export interface InstlSncnCklstResultSaveDto {
+  /** 점검표일련번호 */
   cklstSn: number;
+  /** 점검표항목일련번호 */
   cklstArtclSn: number;
+  /** 점검표검토일련번호 */
   cklstRvwSn: number;
+  /** 검토단계공통코드 */
   rvwStpComCd: string;
+  /** 선택값(Y/N/null) */
   selected: "Y" | "N" | null;
+  /** 담당자검토내용(기술검토의견) */
   picRvwCn?: string | null;
 }
 
 /** 설치인가 신청 - 필수첨부파일 저장 DTO(배열 원소) */
 export interface InstlSncnEsntlAtchFileSaveDto {
+  /** 필수첨부파일아이디 */
   esntlAtchFileId: string;
+  /** 첨부파일그룹아이디 */
   atchFileGroupId: string;
 }
 
+/** 설치인가검토의견 저장 요청 DTO */
+export interface InstlSncnRvwOpnnSaveRequestDto {
+  /** 설치인가문서번호 */
+  instlSncnDocNo: string;
+  /** 검토의견일련번호 */
+  rvwOpnnSn?: number;
+  /** 의견자구분공통코드 */
+  opnrSeComCd?: string;
+  /** 의견자명 */
+  opnrNm?: string;
+  /** 검토결과내용 */
+  rvwRsltCn?: string;
+  /** 검토결과이상여부 */
+  rvwRsltAnmlyYn?: string;
+  /** 첨부파일그룹아이디 */
+  atchFileGroupId?: string;
+}
+
+/** 설치인가 보완요구 저장 DTO(배열 원소) */
+export interface InstlSncnSplmntDmndSaveDto {
+  /** 보완요구 일련번호 */
+  splmntDmndSn?: number;
+  /** 보완항목 공통코드 */
+  splmntArtclComCd?: string;
+  /** 보완요구 내용 */
+  splmntDmndCn?: string;
+  /** 보완요구 일시 */
+  splmntDmndDt?: string;
+  /** 보완요구 첨부파일 그룹 ID */
+  splmntDmndAtchFileGroupId?: string;
+  /** 보완 내용 */
+  splmntCn?: string;
+  /** 보완 담당자 명 */
+  splmntPicNm?: string;
+  /** 보완완료 일시 */
+  splmntCmptnDt?: string;
+  /** 보완 첨부파일 그룹 ID */
+  splmntAtchFileGroupId?: string;
+  /** 완료 여부 */
+  cmptnYn?: string;
+}
+
 /** 설치인가 신청 - 통합 저장 요청 DTO */
 export interface InstlSncnApplySaveRequestDto {
+  /** 기술검토저장구분(SV.저장, CP.검토완료) */
+  techReViewSaveCd?: string;
+  /** 검토단계공통코드(ENV.환경청.EP, KECO.환경공단.TE) */
+  rvwStpCd?: string;
+  /** 설치인가관리 정보 */
   instlSncnMng: InstlSncnMngSaveRequestDto;
+  /** 사업규모 목록 */
   bzScaleList: InstlSncnBzScaleSaveDto[];
+  /** 총사업비 목록 */
   bizCstList: InstlSncnBizCstSaveRequestDto[];
+  /** 체크리스트 검토결과 목록 */
   cklstResultList: InstlSncnCklstResultSaveDto[];
+  /** 체크리스트 검토결과 맵 (rvwStpComCd -> 목록) */
+  cklstResultMap?: Record<string, InstlSncnCklstResultSaveDto[]>;
+  /** 필수첨부파일 목록 */
   esntlAtchFileList: InstlSncnEsntlAtchFileSaveDto[];
+  /** 검토의견 목록 */
+  rvwOpnnList?: InstlSncnRvwOpnnSaveRequestDto[];
+  /** 보완요구 목록 */
+  splmntDmndList?: InstlSncnSplmntDmndSaveDto[];
 }
 
 export type ReviewStepCode = "LOCAL" | "ENV" | "KECO";
diff --git a/apps/as/src/pages/approval-line-management/ui/elapr-tmplt-form-dialog.tsx b/apps/as/src/pages/approval-line-management/ui/elapr-tmplt-form-dialog.tsx
index 3e7f36de1..8aea03c7e 100644
--- a/apps/as/src/pages/approval-line-management/ui/elapr-tmplt-form-dialog.tsx
+++ b/apps/as/src/pages/approval-line-management/ui/elapr-tmplt-form-dialog.tsx
@@ -92,7 +92,7 @@ function ElaprTmpltFormDialog({
           <div className="space-y-2">
             <Label>문서구분</Label>
             <CodeSelect
-              upCd="ASDOCSECD"
+              upCd="ASDOCSE"
               value={docSeComCd}
               onValueChange={(v) => setValue("docSeComCd", v)}
               placeholder="문서구분 선택"
diff --git a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-form-dialog.tsx b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-form-dialog.tsx
index 0f1faf8a1..16d6fed1c 100644
--- a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-form-dialog.tsx
+++ b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-form-dialog.tsx
@@ -94,7 +94,7 @@ function EsntlAtchFileFormDialog({
           <div className="space-y-2">
             <Label>문서구분</Label>
             <CodeSelect
-              upCd="ASDOCSECD"
+              upCd="ASDOCSE"
               value={docSeComCd}
               onValueChange={(v) => setValue("docSeComCd", v, { shouldValidate: true })}
               placeholder="문서구분 선택"
diff --git a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-list.tsx b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-list.tsx
index 661b3a822..62a728073 100644
--- a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-list.tsx
+++ b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-list.tsx
@@ -36,7 +36,7 @@ function EsntlAtchFileList({
   onPaginationChange,
 }: EsntlAtchFileListProps) {
   const { confirm } = useConfirm();
-  const { data: docSeCodes } = useCodeList("ASDOCSECD");
+  const { data: docSeCodes } = useCodeList("ASDOCSE");
 
   const [dialogMode, setDialogMode] = useState<"create" | "edit" | null>(null);
   const [editingRow, setEditingRow] = useState<EsntlAtchFileMng | null>(null);
diff --git a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-mng-page.tsx b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-mng-page.tsx
index 425169983..3e5dbe9bb 100644
--- a/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-mng-page.tsx
+++ b/apps/as/src/pages/esntl-atch-file-mng/ui/esntl-atch-file-mng-page.tsx
@@ -32,7 +32,7 @@ const DEFAULT_SEARCH_PARAMS = {
 };
 
 function EsntlAtchFileMngPage() {
-  const { data: docSeCodes, isPending: isDocSeLoading } = useCodeList("ASDOCSECD");
+  const { data: docSeCodes, isPending: isDocSeLoading } = useCodeList("ASDOCSE");
 
   const [docSeComCd, setDocSeComCd] = useState(ESNTL_ATCH_FILE_ALL_DOC_SE);
   const [pagination, setPagination] = useState<PaginationState>({
diff --git a/apps/as/src/pages/instl-sncn/lib/button-config.ts b/apps/as/src/pages/instl-sncn/lib/button-config.ts
index de262cf62..6b1a542b7 100644
--- a/apps/as/src/pages/instl-sncn/lib/button-config.ts
+++ b/apps/as/src/pages/instl-sncn/lib/button-config.ts
@@ -50,7 +50,7 @@ const ROLE_STATUS_BUTTON_ACTIONS: Record<string, Record<string, InstlSncnViewBut
   },
 };
 
-const ROLE_USER01_ATRZ_STATUS_CODES = ["ER", "EE"] as const;
+const ROLE_USER01_ATRZ_STATUS_CODES = ["ER", "TE"] as const;
 
 const ROLE_USER01_ATRZ_STATUS_ACTIONS: Record<
   string,
@@ -59,7 +59,7 @@ const ROLE_USER01_ATRZ_STATUS_ACTIONS: Record<
   ER: {
     ATRZ01: [INSTL_SNCN_VIEW_BUTTON_ACTION.dsgntRvwr],
   },
-  EE: {
+  TE: {
     ATRZ02: [
       INSTL_SNCN_VIEW_BUTTON_ACTION.rvwStrg,
       INSTL_SNCN_VIEW_BUTTON_ACTION.rvwCmptn,
diff --git a/apps/as/src/pages/instl-sncn/lib/checklist-utils.ts b/apps/as/src/pages/instl-sncn/lib/checklist-utils.ts
index 3d636b3e5..3508e2263 100644
--- a/apps/as/src/pages/instl-sncn/lib/checklist-utils.ts
+++ b/apps/as/src/pages/instl-sncn/lib/checklist-utils.ts
@@ -15,6 +15,7 @@ import type {
 
 import {
   type ChecklistFormState,
+  type ChecklistProgress,
   type ChecklistRowKey,
   type ChecklistStepMap,
   INSTL_PROGRESS_ORDER,
@@ -23,8 +24,12 @@ import {
   ROLE_TO_REVIEW_STEP,
 } from "../model/view-types";
 
-export function buildChecklistRowKey(row: CklstRvwRsltTreeDto): ChecklistRowKey {
-  return `${row.taskSeComCd}_${row.cklstSn}_${row.cklstArtclSn}_${row.cklstRvwSn}_${row.rvwStpComCd ?? "LOCAL"}`;
+export function buildChecklistRowKey(
+  row: CklstRvwRsltTreeDto,
+  reviewStep?: ReviewStepCode,
+): ChecklistRowKey {
+  const step = reviewStep ?? (row.rvwStpComCd as ReviewStepCode) ?? "LOCAL";
+  return `${row.taskSeComCd}_${row.cklstSn}_${row.cklstArtclSn}_${row.cklstRvwSn}_${step}`;
 }
 
 export function groupByReviewStep(rows: CklstRvwRsltTreeDto[]): ChecklistStepMap {
@@ -37,11 +42,9 @@ export function groupByReviewStep(rows: CklstRvwRsltTreeDto[]): ChecklistStepMap
 }
 
 export function getProgressStepCount(prgrsSttsComCd?: string): number {
-  const idx = INSTL_PROGRESS_ORDER.indexOf(
-    (prgrsSttsComCd ?? "ST") as (typeof INSTL_PROGRESS_ORDER)[number],
-  );
-  if (idx <= INSTL_PROGRESS_ORDER.indexOf("ST")) return 1;
-  if (idx <= INSTL_PROGRESS_ORDER.indexOf("TP")) return 2;
+  const idx = INSTL_PROGRESS_ORDER.indexOf(prgrsSttsComCd as (typeof INSTL_PROGRESS_ORDER)[number]);
+  if (idx <= INSTL_PROGRESS_ORDER.indexOf("SV")) return 1;
+  if (idx <= INSTL_PROGRESS_ORDER.indexOf("LE")) return 2;
   return 3;
 }
 
@@ -77,6 +80,62 @@ export function filterChecklistRows(
     );
 }
 
+export function getChecklistDisplayRows(
+  rows: CklstRvwRsltTreeDto[],
+  taskCode?: string | null,
+): CklstRvwRsltTreeDto[] {
+  const filtered = filterChecklistRows(rows, taskCode ?? null);
+  const seen = new Set<string>();
+  const deduped: CklstRvwRsltTreeDto[] = [];
+
+  for (const row of filtered) {
+    const dedupeKey = `${row.taskSeComCd}_${row.cklstRvwSn}`;
+    if (seen.has(dedupeKey)) continue;
+    seen.add(dedupeKey);
+    deduped.push(row);
+  }
+
+  return deduped;
+}
+
+export function computeChecklistProgress(
+  rows: CklstRvwRsltTreeDto[],
+  results: ChecklistFormState["results"],
+): ChecklistProgress {
+  const activeRows = rows.filter((row) => row.bchckUseYn === "Y");
+  const total = activeRows.length;
+  const completed = activeRows.reduce((acc, row) => {
+    const key = buildChecklistRowKey(row);
+    const val = results[key] ?? row.rvwRsltAnmlyYn ?? "";
+    return acc + (val ? 1 : 0);
+  }, 0);
+  const percent = total > 0 ? Math.round((completed / total) * 100) : 0;
+  return { total, completed, percent };
+}
+
+export function filterChecklistRowsByReviewStep(
+  rows: CklstRvwRsltTreeDto[],
+  reviewStep: ReviewStepCode,
+): CklstRvwRsltTreeDto[] {
+  return rows.filter((row) => row.rvwStpComCd === reviewStep);
+}
+
+export function computeReviewStepChecklistProgress(
+  rows: CklstRvwRsltTreeDto[],
+  results: ChecklistFormState["results"],
+  reviewStep: ReviewStepCode,
+): ChecklistProgress {
+  const activeRows = getChecklistDisplayRows(rows).filter((row) => row.bchckUseYn === "Y");
+  const total = activeRows.length;
+  const completed = activeRows.reduce((acc, row) => {
+    const key = buildChecklistRowKey(row, reviewStep);
+    const val = results[key];
+    return acc + (val === "Y" || val === "N" ? 1 : 0);
+  }, 0);
+  const percent = total > 0 ? Math.round((completed / total) * 100) : 0;
+  return { total, completed, percent };
+}
+
 export function buildChecklistFormState(rows: CklstRvwRsltTreeDto[]): ChecklistFormState {
   const results: ChecklistFormState["results"] = {};
   const comments: ChecklistFormState["comments"] = {};
@@ -87,7 +146,57 @@ export function buildChecklistFormState(rows: CklstRvwRsltTreeDto[]): ChecklistF
     }
     if (row.picRvwCn) comments[key] = row.picRvwCn;
   });
-  return { results, comments };
+  return {
+    results,
+    comments,
+    progress: computeChecklistProgress(rows, results),
+  };
+}
+
+export function mergeChecklistFormStateFromServer(
+  prev: ChecklistFormState,
+  allRows: CklstRvwRsltTreeDto[],
+): ChecklistFormState {
+  const results = { ...prev.results };
+  const comments = { ...prev.comments };
+
+  for (const row of allRows) {
+    const step = row.rvwStpComCd as ReviewStepCode | undefined;
+    if (!step || !REVIEW_STEP_CODES.includes(step)) continue;
+
+    const key = buildChecklistRowKey(row);
+    if ((row.rvwRsltAnmlyYn === "Y" || row.rvwRsltAnmlyYn === "N") && results[key] === undefined) {
+      results[key] = row.rvwRsltAnmlyYn;
+    }
+    if (row.picRvwCn && !comments[key]) {
+      comments[key] = row.picRvwCn;
+    }
+  }
+
+  return {
+    results,
+    comments,
+    progress: computeChecklistProgress(getChecklistDisplayRows(allRows), results),
+  };
+}
+
+export function patchChecklistFormState(
+  prev: ChecklistFormState,
+  patch: Partial<Pick<ChecklistFormState, "results" | "comments">>,
+  allRows: CklstRvwRsltTreeDto[],
+  reviewStep?: ReviewStepCode,
+): ChecklistFormState {
+  const results = patch.results ?? prev.results;
+  const comments = patch.comments ?? prev.comments;
+  const progress = reviewStep
+    ? computeReviewStepChecklistProgress(allRows, results, reviewStep)
+    : computeChecklistProgress(getChecklistDisplayRows(allRows), results);
+
+  return {
+    results,
+    comments,
+    progress,
+  };
 }
 
 export function toCklstSaveDto(
@@ -95,20 +204,18 @@ export function toCklstSaveDto(
   formState: ChecklistFormState,
   reviewStep: ReviewStepCode,
 ): InstlSncnCklstResultSaveDto[] {
-  return rows
+  return getChecklistDisplayRows(rows)
     .filter((row) => row.bchckUseYn === "Y")
     .map((row) => {
-      const key = buildChecklistRowKey(row);
-      const selected =
-        formState.results[key] ??
-        (row.rvwRsltAnmlyYn === "Y" || row.rvwRsltAnmlyYn === "N" ? row.rvwRsltAnmlyYn : null);
+      const key = buildChecklistRowKey(row, reviewStep);
+      const selected = formState.results[key] ?? null;
       return {
         cklstSn: row.cklstSn,
         cklstArtclSn: row.cklstArtclSn,
         cklstRvwSn: row.cklstRvwSn,
         rvwStpComCd: reviewStep,
         selected,
-        picRvwCn: formState.comments[key] ?? row.picRvwCn ?? null,
+        picRvwCn: formState.comments[key] ?? null,
       };
     });
 }
@@ -169,6 +276,20 @@ export function buildSavePayload(
   };
 }
 
+export function buildTechReviewReplyPayload(
+  data: InstlSncnMngDetResponse,
+  checklistFormState: ChecklistFormState,
+  reviewStep: ReviewStepCode,
+  prgrsSttsComCd: string,
+  techReViewSaveCd: string,
+): InstlSncnApplySaveRequestDto {
+  return {
+    ...buildSavePayload(data, checklistFormState, reviewStep, prgrsSttsComCd),
+    techReViewSaveCd,
+    rvwStpCd: reviewStep,
+  };
+}
+
 export function buildTechReviewPayload(
   det: InstlSncnMngResponseDto,
   cklstResultList: InstlSncnCklstResultSaveDto[],
diff --git a/apps/as/src/pages/instl-sncn/lib/use-checklist-form-state.ts b/apps/as/src/pages/instl-sncn/lib/use-checklist-form-state.ts
new file mode 100644
index 000000000..819f4ed82
--- /dev/null
+++ b/apps/as/src/pages/instl-sncn/lib/use-checklist-form-state.ts
@@ -0,0 +1,57 @@
+import { useCallback, useEffect, useState } from "react";
+
+import type { CklstRvwRsltTreeDto, ReviewStepCode } from "@/entities/instl-sncn";
+
+import { type ChecklistFormState, DEFAULT_CHECKLIST_PROGRESS } from "../model/view-types";
+
+import { mergeChecklistFormStateFromServer, patchChecklistFormState } from "./checklist-utils";
+
+const EMPTY_CKLST_RESULT_LIST: CklstRvwRsltTreeDto[] = [];
+
+function isSameChecklistFormState(a: ChecklistFormState, b: ChecklistFormState): boolean {
+  if (
+    a.progress.total !== b.progress.total ||
+    a.progress.completed !== b.progress.completed ||
+    a.progress.percent !== b.progress.percent
+  ) {
+    return false;
+  }
+
+  const aResultKeys = Object.keys(a.results);
+  if (aResultKeys.length !== Object.keys(b.results).length) return false;
+  if (!aResultKeys.every((key) => a.results[key] === b.results[key])) return false;
+
+  const aCommentKeys = Object.keys(a.comments);
+  if (aCommentKeys.length !== Object.keys(b.comments).length) return false;
+
+  return aCommentKeys.every((key) => a.comments[key] === b.comments[key]);
+}
+
+function useChecklistFormState(cklstResultList: CklstRvwRsltTreeDto[] = EMPTY_CKLST_RESULT_LIST) {
+  const [formState, setFormState] = useState<ChecklistFormState>({
+    results: {},
+    comments: {},
+    progress: DEFAULT_CHECKLIST_PROGRESS,
+  });
+
+  useEffect(() => {
+    setFormState((prev) => {
+      const next = mergeChecklistFormStateFromServer(prev, cklstResultList);
+      return isSameChecklistFormState(prev, next) ? prev : next;
+    });
+  }, [cklstResultList]);
+
+  const patchFormState = useCallback(
+    (
+      patch: Partial<Pick<ChecklistFormState, "results" | "comments">>,
+      reviewStep?: ReviewStepCode,
+    ) => {
+      setFormState((prev) => patchChecklistFormState(prev, patch, cklstResultList, reviewStep));
+    },
+    [cklstResultList],
+  );
+
+  return { formState, setFormState, patchFormState };
+}
+
+export { EMPTY_CKLST_RESULT_LIST, useChecklistFormState };
diff --git a/apps/as/src/pages/instl-sncn/model/view-types.ts b/apps/as/src/pages/instl-sncn/model/view-types.ts
index 0a555e8a4..a6fc0b08c 100644
--- a/apps/as/src/pages/instl-sncn/model/view-types.ts
+++ b/apps/as/src/pages/instl-sncn/model/view-types.ts
@@ -26,9 +26,22 @@ export type {
 
 export type ChecklistRowKey = string;
 
+export interface ChecklistProgress {
+  total: number;
+  completed: number;
+  percent: number;
+}
+
+export const DEFAULT_CHECKLIST_PROGRESS: ChecklistProgress = {
+  total: 0,
+  completed: 0,
+  percent: 0,
+};
+
 export interface ChecklistFormState {
   results: Record<ChecklistRowKey, "Y" | "N">;
   comments: Record<ChecklistRowKey, string>;
+  progress: ChecklistProgress;
 }
 
 export type ChecklistStepMap = Record<ReviewStepCode, CklstRvwRsltTreeDto[]>;
@@ -48,17 +61,23 @@ export const TASK_CODE_LABELS: Record<string, string> = {
 };
 
 export const INSTL_PROGRESS_ORDER = [
+  // ROLE_USER05
   "SV",
-  "ST",
-  "LE",
-  "ER",
-  "EE",
-  "TE",
-  "TS",
-  "TR",
-  "TP",
-  "EP",
+  "SL",
   "TA",
+
+  // ROLE_USER04
+  "ST",
+  "EP",
+
+  // ROLE_USER03
+  "LE",
+  "TP",
+
+  // ROLE_USER01
+  "ER",
+  "TE",
+
   "TB",
 ] as const;
 
diff --git a/apps/as/src/pages/instl-sncn/ui/components/checklist-task-panel.tsx b/apps/as/src/pages/instl-sncn/ui/components/checklist-task-panel.tsx
index 9ba74c0ec..344e1b7c3 100644
--- a/apps/as/src/pages/instl-sncn/ui/components/checklist-task-panel.tsx
+++ b/apps/as/src/pages/instl-sncn/ui/components/checklist-task-panel.tsx
@@ -12,12 +12,13 @@ import {
   Textarea,
 } from "@common/components";
 
-import { buildChecklistRowKey } from "../../lib/checklist-utils";
+import { buildChecklistRowKey, patchChecklistFormState } from "../../lib/checklist-utils";
 import { type ChecklistFormState, ROLE_TO_REVIEW_STEP } from "../../model/view-types";
 
 interface ChecklistTaskPanelProps {
   selectedReviewStep: ReviewStepCode;
   selectedRows: CklstRvwRsltTreeDto[];
+  allRows: CklstRvwRsltTreeDto[];
   formState: ChecklistFormState;
   setFormState: Dispatch<SetStateAction<ChecklistFormState>>;
   userRoleCode?: string;
@@ -26,6 +27,7 @@ interface ChecklistTaskPanelProps {
 function ChecklistTaskPanel({
   selectedReviewStep,
   selectedRows,
+  allRows,
   formState,
   setFormState,
   userRoleCode,
@@ -64,7 +66,7 @@ function ChecklistTaskPanel({
               </TableRow>
             ) : (
               selectedRows.map((row) => {
-                const key = buildChecklistRowKey(row);
+                const key = buildChecklistRowKey(row, selectedReviewStep);
                 const isFieldVisible = row.bchckUseYn === "Y";
                 const isLocalReviewStep = selectedReviewStep === "LOCAL";
 
@@ -74,16 +76,11 @@ function ChecklistTaskPanel({
                     <TableCell
                       className="pl-2 !text-left text-[1.2rem] text-gray-600"
                       style={{ paddingLeft: `${Math.max(0, row.treeLevel - 1) * 16 + 8}px` }}
+                      colSpan={isFieldVisible ? 0 : isLocalReviewStep ? 3 : 4}
                     >
-                      {row.treeLevel > 1 ? "└ " : ""}
                       {row.rvwCn}
                     </TableCell>
-                    {!isFieldVisible ? (
-                      <>
-                        <TableCell className="bg-muted" />
-                        <TableCell className="bg-muted" />
-                      </>
-                    ) : (
+                    {isFieldVisible && (
                       <>
                         <TableCell className="text-center">
                           <input
@@ -94,10 +91,14 @@ function ChecklistTaskPanel({
                             readOnly={!isStepEditable}
                             onChange={() => {
                               if (!isStepEditable) return;
-                              setFormState((prev) => ({
-                                ...prev,
-                                results: { ...prev.results, [key]: "Y" },
-                              }));
+                              setFormState((prev) =>
+                                patchChecklistFormState(
+                                  prev,
+                                  { results: { ...prev.results, [key]: "Y" } },
+                                  allRows,
+                                  selectedReviewStep,
+                                ),
+                              );
                             }}
                             className={cn(isStepEditable ? "cursor-pointer" : "cursor-not-allowed")}
                           />
@@ -111,37 +112,43 @@ function ChecklistTaskPanel({
                             readOnly={!isStepEditable}
                             onChange={() => {
                               if (!isStepEditable) return;
-                              setFormState((prev) => ({
-                                ...prev,
-                                results: { ...prev.results, [key]: "N" },
-                              }));
+                              setFormState((prev) =>
+                                patchChecklistFormState(
+                                  prev,
+                                  { results: { ...prev.results, [key]: "N" } },
+                                  allRows,
+                                  selectedReviewStep,
+                                ),
+                              );
                             }}
                             className={cn(isStepEditable ? "cursor-pointer" : "cursor-not-allowed")}
                           />
                         </TableCell>
                       </>
                     )}
-                    {!isLocalReviewStep ? (
-                      <TableCell className={`text-left ${isFieldVisible ? "" : "bg-muted"}`}>
-                        {isFieldVisible && (
-                          <Textarea
-                            className={cn(
-                              "min-h-[6rem] !text-xl",
-                              isStepEditable ? "cursor-pointer" : "cursor-not-allowed",
-                            )}
-                            value={formState.comments[key] ?? ""}
-                            readOnly={!isStepEditable}
-                            onChange={(event) => {
-                              if (!isStepEditable) return;
-                              setFormState((prev) => ({
-                                ...prev,
-                                comments: { ...prev.comments, [key]: event.target.value },
-                              }));
-                            }}
-                          />
-                        )}
+                    {!isLocalReviewStep && isFieldVisible && (
+                      <TableCell className="text-left">
+                        <Textarea
+                          className={cn(
+                            "min-h-[6rem] !text-xl",
+                            isStepEditable ? "cursor-pointer" : "cursor-not-allowed",
+                          )}
+                          value={formState.comments[key] ?? ""}
+                          readOnly={!isStepEditable}
+                          onChange={(event) => {
+                            if (!isStepEditable) return;
+                            setFormState((prev) =>
+                              patchChecklistFormState(
+                                prev,
+                                { comments: { ...prev.comments, [key]: event.target.value } },
+                                allRows,
+                                selectedReviewStep,
+                              ),
+                            );
+                          }}
+                        />
                       </TableCell>
-                    ) : null}
+                    )}
                   </TableRow>
                 );
               })
diff --git a/apps/as/src/pages/instl-sncn/ui/components/floating-action-buttons.tsx b/apps/as/src/pages/instl-sncn/ui/components/floating-action-buttons.tsx
index 7b0240a6c..a23b3af39 100644
--- a/apps/as/src/pages/instl-sncn/ui/components/floating-action-buttons.tsx
+++ b/apps/as/src/pages/instl-sncn/ui/components/floating-action-buttons.tsx
@@ -24,8 +24,12 @@ import {
   type InstlSncnViewButtonAction,
   needsRoleUser01AtrzResolve,
 } from "../../lib/button-config";
-import { buildSavePayload } from "../../lib/checklist-utils";
-import { type ChecklistFormState, ROLE_TO_REVIEW_STEP } from "../../model/view-types";
+import {
+  buildSavePayload,
+  buildTechReviewReplyPayload,
+  computeReviewStepChecklistProgress,
+} from "../../lib/checklist-utils";
+import { type ChecklistFormState } from "../../model/view-types";
 
 import { ElaprTmpltPickerDialog } from "./elapr-tmplt-picker-dialog";
 import { TextInputDialog } from "./text-input-dialog";
@@ -57,6 +61,7 @@ function FloatingActionButtons({
   const [isProcessing, setIsProcessing] = useState(false);
   const [activeDialog, setActiveDialog] = useState<ActiveDialog>(null);
 
+  const docNo = data.detDto.instlSncnDocNo;
   const isRegister = data.detDto.rgtr === userInfo?.userUnqId;
 
   const needsAtrzResolve = needsRoleUser01AtrzResolve(dtlInstCd, prgrsSttsComCd);
@@ -123,11 +128,10 @@ function FloatingActionButtons({
   }
 
   async function handleStrgClick() {
-    const userReviewStep = dtlInstCd ? (ROLE_TO_REVIEW_STEP[dtlInstCd] ?? "LOCAL") : "LOCAL";
     const payload: InstlSncnApplySaveRequestDto = buildSavePayload(
       data,
       checklistFormState,
-      userReviewStep,
+      "LOCAL",
       "SV",
     );
 
@@ -139,16 +143,20 @@ function FloatingActionButtons({
   }
 
   async function handleAplyClick() {
-    const userReviewStep = dtlInstCd ? (ROLE_TO_REVIEW_STEP[dtlInstCd] ?? "LOCAL") : "LOCAL";
+    const { percent } = computeReviewStepChecklistProgress(
+      data.cklstResultList ?? [],
+      checklistFormState.results,
+      "LOCAL",
+    );
     const payload: InstlSncnApplySaveRequestDto = buildSavePayload(
       data,
       checklistFormState,
-      userReviewStep,
+      "LOCAL",
       "ST",
     );
 
-    if (payload.cklstResultList?.some((item) => item.selected === null)) {
-      alert("모든 검토항목을 검토 완료해야 신청 가능합니다.");
+    if (percent !== 100) {
+      alert("모든 체크리스트 항목을 체크해야 신청이 가능합니다.");
       return;
     }
 
@@ -171,9 +179,25 @@ function FloatingActionButtons({
     router.push("/instl-sncn");
   }
 
+  async function handleInstlSncnAncmntClick() {
+    const payload: DocPrgrsUpdateRequestDto = {
+      docNo,
+      docSeComCd,
+      prgrsSttsComCd: "TB",
+    };
+    await executeAction({
+      action: INSTL_SNCN_VIEW_BUTTON_ACTION.instlSncnAncmnt,
+      request: payload,
+      successMessage: "고시되었습니다.",
+    });
+    queryClient.invalidateQueries({
+      queryKey: instlSncnKeys.list(),
+    });
+  }
+
   async function handleEnvoSbmsnClick() {
     const payload: DocPrgrsUpdateRequestDto = {
-      docNo: data.detDto.instlSncnDocNo,
+      docNo,
       docSeComCd,
       prgrsSttsComCd: "LE",
     };
@@ -191,7 +215,7 @@ function FloatingActionButtons({
     if (!(await confirm("반려하시겠습니까?"))) return;
 
     const payload: DocPrgrsUpdateRequestDto = {
-      docNo: data.detDto.instlSncnDocNo,
+      docNo,
       docSeComCd,
       prgrsSttsComCd: "SV",
     };
@@ -205,9 +229,48 @@ function FloatingActionButtons({
     });
   }
 
+  async function handleSncnAprvClick() {
+    const payload: DocPrgrsUpdateRequestDto = {
+      docNo,
+      docSeComCd,
+      prgrsSttsComCd: "TA",
+    };
+    await executeAction({
+      action: INSTL_SNCN_VIEW_BUTTON_ACTION.sncnAprv,
+      request: payload,
+      successMessage: "인가승인되었습니다.",
+    });
+    queryClient.invalidateQueries({
+      queryKey: instlSncnKeys.list(),
+    });
+  }
+
+  async function handleRvwRplyClick() {
+    const { percent } = computeReviewStepChecklistProgress(
+      data.cklstResultList ?? [],
+      checklistFormState.results,
+      "ENV",
+    );
+
+    if (percent !== 100) {
+      alert("모든 체크리스트 항목을 체크해야 검토결과 회신이 가능합니다.");
+      return;
+    }
+
+    if (!(await confirm("검토결과를 회신하시겠습니까?"))) return;
+
+    const payload = buildTechReviewReplyPayload(data, checklistFormState, "ENV", "EP", "CP");
+
+    await executeAction({
+      action: INSTL_SNCN_VIEW_BUTTON_ACTION.rvwRply,
+      request: payload,
+      successMessage: "검토결과 회신이 완료되었습니다.",
+    });
+  }
+
   async function handleRqstTechRvwClick() {
     const payload: DocPrgrsUpdateRequestDto = {
-      docNo: data.detDto.instlSncnDocNo,
+      docNo,
       docSeComCd,
       prgrsSttsComCd: "ER",
     };
@@ -235,6 +298,16 @@ function FloatingActionButtons({
     });
   }
 
+  async function handleRvwStrgClick() {
+    const payload = buildTechReviewReplyPayload(data, checklistFormState, "KECO", "TE", "SV");
+
+    await executeAction({
+      action: INSTL_SNCN_VIEW_BUTTON_ACTION.rvwStrg,
+      request: payload,
+      successMessage: "저장되었습니다.",
+    });
+  }
+
   function handleDmndSplmntClick() {
     setActiveDialog("dmndSplmnt");
   }
@@ -286,12 +359,7 @@ function FloatingActionButtons({
             </Button>
           )}
           {shouldShowButton(INSTL_SNCN_VIEW_BUTTON_ACTION.instlSncnAncmnt) && (
-            <Button
-              onClick={() =>
-                void executeAction({ action: INSTL_SNCN_VIEW_BUTTON_ACTION.instlSncnAncmnt })
-              }
-              disabled={isProcessing}
-            >
+            <Button onClick={handleInstlSncnAncmntClick} disabled={isProcessing}>
               설치인가 고시
             </Button>
           )}
@@ -306,19 +374,12 @@ function FloatingActionButtons({
             </Button>
           )}
           {shouldShowButton(INSTL_SNCN_VIEW_BUTTON_ACTION.sncnAprv) && (
-            <Button
-              onClick={() => void executeAction({ action: INSTL_SNCN_VIEW_BUTTON_ACTION.sncnAprv })}
-              disabled={isProcessing}
-            >
+            <Button onClick={handleSncnAprvClick} disabled={isProcessing}>
               인가승인
             </Button>
           )}
           {shouldShowButton(INSTL_SNCN_VIEW_BUTTON_ACTION.rvwRply) && (
-            <Button
-              color="green"
-              onClick={() => void executeAction({ action: INSTL_SNCN_VIEW_BUTTON_ACTION.rvwRply })}
-              disabled={isProcessing}
-            >
+            <Button color="green" onClick={handleRvwRplyClick} disabled={isProcessing}>
               검토결과 회신
             </Button>
           )}
@@ -333,10 +394,7 @@ function FloatingActionButtons({
             </Button>
           )}
           {shouldShowButton(INSTL_SNCN_VIEW_BUTTON_ACTION.rvwStrg) && (
-            <Button
-              onClick={() => void executeAction({ action: INSTL_SNCN_VIEW_BUTTON_ACTION.rvwStrg })}
-              disabled={isProcessing}
-            >
+            <Button onClick={handleRvwStrgClick} disabled={isProcessing}>
               저장
             </Button>
           )}
@@ -434,8 +492,12 @@ async function handleSplmntCmptn(context: ActionHandlerContext): Promise<void> {
 }
 
 async function handleInstlSncnAncmnt(context: ActionHandlerContext): Promise<void> {
-  // TODO: 고시 처리 API 호출
-  context.onSuccess?.();
+  try {
+    await instlSncnService.changePrgrsSttsComCd(context.request);
+    context.onSuccess?.();
+  } catch (error) {
+    context.onError?.(error as Error);
+  }
 }
 
 async function handleEnvoSbmsn(
@@ -459,18 +521,32 @@ async function handleRjct(context: ActionHandlerContext<DocPrgrsUpdateRequestDto
 }
 
 async function handleSncnAprv(context: ActionHandlerContext): Promise<void> {
-  // TODO: 인가승인 API 호출
-  context.onSuccess?.();
+  try {
+    await instlSncnService.changePrgrsSttsComCd(context.request);
+    context.onSuccess?.();
+  } catch (error) {
+    context.onError?.(error as Error);
+  }
 }
 
-async function handleRvwRply(context: ActionHandlerContext): Promise<void> {
-  // TODO: 검토결과 회신 API 호출
-  context.onSuccess?.();
+async function handleRvwRply(
+  context: ActionHandlerContext<InstlSncnApplySaveRequestDto>,
+): Promise<void> {
+  try {
+    await instlSncnService.techReview(context.data.detDto.instlSncnDocNo, context.request);
+    context.onSuccess?.();
+  } catch (error) {
+    context.onError?.(error as Error);
+  }
 }
 
 async function handleRqstTechRvw(context: ActionHandlerContext): Promise<void> {
-  // TODO: 기술검토 의뢰 API 호출
-  context.onSuccess?.();
+  try {
+    await instlSncnService.changePrgrsSttsComCd(context.request);
+    context.onSuccess?.();
+  } catch (error) {
+    context.onError?.(error as Error);
+  }
 }
 
 async function handleDsgntRvwr(context: ActionHandlerContext<ElaprDmndSaveRequest>): Promise<void> {
@@ -482,9 +558,15 @@ async function handleDsgntRvwr(context: ActionHandlerContext<ElaprDmndSaveReques
   }
 }
 
-async function handleRvwStrg(context: ActionHandlerContext): Promise<void> {
-  // TODO: 검토저장 API 호출
-  context.onSuccess?.();
+async function handleRvwStrg(
+  context: ActionHandlerContext<InstlSncnApplySaveRequestDto>,
+): Promise<void> {
+  try {
+    await instlSncnService.techReview(context.data.detDto.instlSncnDocNo, context.request);
+    context.onSuccess?.();
+  } catch (error) {
+    context.onError?.(error as Error);
+  }
 }
 
 async function handleRvwCmptn(context: ActionHandlerContext): Promise<void> {
diff --git a/apps/as/src/pages/instl-sncn/ui/instl-view-page.tsx b/apps/as/src/pages/instl-sncn/ui/instl-view-page.tsx
index 3eff839c1..0a01a8d4c 100644
--- a/apps/as/src/pages/instl-sncn/ui/instl-view-page.tsx
+++ b/apps/as/src/pages/instl-sncn/ui/instl-view-page.tsx
@@ -6,7 +6,7 @@ import { useUserStore } from "@/shared/lib";
 import { useInstlSncnDetail } from "@/entities/instl-sncn";
 import { Skeleton } from "@common/components";
 
-import { type ChecklistFormState } from "../model/view-types";
+import { EMPTY_CKLST_RESULT_LIST, useChecklistFormState } from "../lib/use-checklist-form-state";
 
 import { FloatingActionButtons } from "./components/floating-action-buttons";
 import { AttachmentsSection } from "./sections/attachments-section";
@@ -24,10 +24,8 @@ interface InstlViewPageProps {
 function InstlViewPage({ id }: InstlViewPageProps) {
   const userInfo = useUserStore((state) => state.userInfo);
   const { data, isLoading, isError } = useInstlSncnDetail(id);
-  const [checklistFormState, setChecklistFormState] = useState<ChecklistFormState>({
-    results: {},
-    comments: {},
-  });
+  const { formState: checklistFormState, setFormState: setChecklistFormState } =
+    useChecklistFormState(data?.cklstResultList ?? EMPTY_CKLST_RESULT_LIST);
 
   if (isLoading) {
     return (
diff --git a/apps/as/src/pages/instl-sncn/ui/sections/checklist-section.tsx b/apps/as/src/pages/instl-sncn/ui/sections/checklist-section.tsx
index 8eecd947a..050f14452 100644
--- a/apps/as/src/pages/instl-sncn/ui/sections/checklist-section.tsx
+++ b/apps/as/src/pages/instl-sncn/ui/sections/checklist-section.tsx
@@ -6,10 +6,9 @@ import type { CklstRvwRsltTreeDto, ReviewStepCode } from "@/entities/instl-sncn"
 import { Tabs, TabsContent, TabsList, TabsTrigger } from "@common/components";
 
 import {
-  buildChecklistFormState,
-  buildChecklistRowKey,
+  computeReviewStepChecklistProgress,
   extractTaskCodes,
-  filterChecklistRows,
+  getChecklistDisplayRows,
   getVisibleReviewSteps,
 } from "../../lib/checklist-utils";
 import {
@@ -39,7 +38,6 @@ function ChecklistSection({
     () => getVisibleReviewSteps(prgrsSttsComCd, userRoleCode),
     [prgrsSttsComCd, userRoleCode],
   );
-
   const taskCodes = useMemo(() => extractTaskCodes(cklstResultList), [cklstResultList]);
 
   const [selectedReviewStep, setSelectedReviewStep] = useState<ReviewStepCode>("LOCAL");
@@ -62,26 +60,13 @@ function ChecklistSection({
     }
   }, [taskCodes, selectedTaskCode]);
 
-  const selectedRows = useMemo(
-    () => filterChecklistRows(cklstResultList, selectedTaskCode),
-    [cklstResultList, selectedTaskCode],
+  const progress = useMemo(
+    () =>
+      computeReviewStepChecklistProgress(cklstResultList, formState.results, selectedReviewStep),
+    [cklstResultList, formState.results, selectedReviewStep],
   );
 
-  useEffect(() => {
-    setFormState(buildChecklistFormState(selectedRows));
-  }, [selectedRows]);
-
-  const cklstStats = useMemo(() => {
-    const rows = selectedRows.filter((row) => row.bchckUseYn === "Y");
-    const total = rows.length;
-    const completed = rows.reduce((acc, row) => {
-      const key = buildChecklistRowKey(row);
-      const val = formState.results[key] ?? row.rvwRsltAnmlyYn ?? "";
-      return acc + (val ? 1 : 0);
-    }, 0);
-    const percent = total > 0 ? Math.round((completed / total) * 100) : 0;
-    return { total, completed, percent };
-  }, [selectedRows, formState.results]);
+  const { total, completed, percent } = progress;
 
   return (
     <SectionCollapsible title="체크리스트">
@@ -122,9 +107,8 @@ function ChecklistSection({
                 ))}
               </TabsList>
               <div className="shrink-0 pb-1 text-lg text-muted-foreground">
-                총합: <strong>{cklstStats.total}</strong> · 완료:{" "}
-                <strong>{cklstStats.completed}</strong> · 진행률:{" "}
-                <strong>{cklstStats.percent}%</strong>
+                총합: <strong>{total}</strong> · 완료: <strong>{completed}</strong> · 진행률:{" "}
+                <strong>{percent}%</strong>
               </div>
             </div>
 
@@ -132,7 +116,8 @@ function ChecklistSection({
               <TabsContent key={code} value={code} className="mt-0 border-0 p-0 shadow-none ring-0">
                 <ChecklistTaskPanel
                   selectedReviewStep={selectedReviewStep}
-                  selectedRows={selectedRows}
+                  selectedRows={getChecklistDisplayRows(cklstResultList, code)}
+                  allRows={cklstResultList}
                   formState={formState}
                   setFormState={setFormState}
                   userRoleCode={userRoleCode}