diff --git a/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi-toolbar.tsx b/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi-toolbar.tsx
index 0723050cb..39123f09d 100644
--- a/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi-toolbar.tsx
+++ b/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi-toolbar.tsx
@@ -1,12 +1,17 @@
 "use client";
 
-import { Download, Fullscreen, Save } from "lucide-react";
+import { useId } from "react";
 
-import { Button } from "@common/components";
+import { Download, FolderOpen, Fullscreen, Save } from "lucide-react";
+
+import { Button, cn } from "@common/components";
+
+const WEBHYP_DEV_MODE = process.env.NEXT_PUBLIC_WEBHYP_DEV_MODE === "true";
 
 interface HangulGiangiToolbarProps {
   isBusy?: boolean;
   canSave?: boolean;
+  onOpen: (file: File) => void;
   onSave: () => void;
   onDownload: () => void;
   onFullscreen: () => void;
@@ -15,12 +20,51 @@ interface HangulGiangiToolbarProps {
 function HangulGiangiToolbar({
   isBusy = false,
   canSave = true,
+  onOpen,
   onSave,
   onDownload,
   onFullscreen,
 }: HangulGiangiToolbarProps) {
+  const openInputId = useId();
+
   return (
     <div className="flex w-full flex-nowrap items-center gap-2 border-b border-border bg-background p-3">
+      {WEBHYP_DEV_MODE && (
+        <label
+          htmlFor={openInputId}
+          className={cn("cursor-pointer", isBusy && "pointer-events-none")}
+        >
+          <input
+            id={openInputId}
+            type="file"
+            accept=".hwpx,application/haansofthwpx"
+            disabled={isBusy}
+            className="peer sr-only"
+            aria-label="열기"
+            onChange={(event) => {
+              const file = event.target.files?.[0];
+              if (file) onOpen(file);
+              event.target.value = "";
+            }}
+          />
+          <Button
+            type="button"
+            color="white"
+            size="sm"
+            disabled={isBusy}
+            className={cn(
+              "peer-focus-visible:ring-2 peer-focus-visible:ring-ring peer-focus-visible:ring-offset-2",
+              isBusy && "pointer-events-none opacity-50",
+            )}
+            asChild
+          >
+            <span>
+              <FolderOpen className="!size-5" />
+              열기
+            </span>
+          </Button>
+        </label>
+      )}
       {canSave && (
         <Button type="button" color="white" size="sm" disabled={isBusy} onClick={onSave}>
           <Save className="!size-5" />
diff --git a/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi.tsx b/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi.tsx
index 000da646a..16663faa2 100644
--- a/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi.tsx
+++ b/apps/as/src/widgets/hangulgiangi/ui/hangul-giangi.tsx
@@ -70,43 +70,46 @@ function HangulGiangi({
     return () => window.clearInterval(timer);
   }, [isCtrlReady, onReady]);
 
-  const handleOpen = useCallback(() => {
-    const ctrl = resolveHwpCtrl(iframeRef.current, isCtrlReady);
-    if (!ctrl) return;
+  const openHwpxBlob = useCallback(
+    (blob: Blob, fileName: string) => {
+      const ctrl = resolveHwpCtrl(iframeRef.current, isCtrlReady);
+      if (!ctrl) return;
 
-    setIsBusy(true);
-    openingDocumentKeyRef.current = documentKey;
-    attemptedDocumentKeyRef.current = documentKey;
-    try {
-      const documentFile = new File([documentBlob], documentFileName, {
-        type: HWPX_CONTENT_TYPE,
-      });
-      const isAccepted = ctrl.Open(
-        documentFile,
-        "HWPX",
-        "",
-        (result) => {
-          const callbackDocumentKey = getCallbackDocumentKey(result.CallbackUserData, documentKey);
-          if (openingDocumentKeyRef.current !== callbackDocumentKey) return;
+      setIsBusy(true);
+      openingDocumentKeyRef.current = documentKey;
+      attemptedDocumentKeyRef.current = documentKey;
+      try {
+        const documentFile = new File([blob], fileName, {
+          type: HWPX_CONTENT_TYPE,
+        });
+        const isAccepted = ctrl.Open(
+          documentFile,
+          "HWPX",
+          "",
+          (result) => {
+            const callbackDocumentKey = getCallbackDocumentKey(result.CallbackUserData, documentKey);
+            if (openingDocumentKeyRef.current !== callbackDocumentKey) return;
 
-          openingDocumentKeyRef.current = null;
-          setIsBusy(false);
-          if (!result.result) return;
+            openingDocumentKeyRef.current = null;
+            setIsBusy(false);
+            if (!result.result) return;
 
-          openedDocumentKeyRef.current = callbackDocumentKey;
-        },
-        { documentKey } satisfies DocumentCallbackUserData,
-      );
+            openedDocumentKeyRef.current = callbackDocumentKey;
+          },
+          { documentKey } satisfies DocumentCallbackUserData,
+        );
 
-      if (isAccepted) return;
+        if (isAccepted) return;
 
-      openingDocumentKeyRef.current = null;
-      setIsBusy(false);
-    } catch {
-      openingDocumentKeyRef.current = null;
-      setIsBusy(false);
-    }
-  }, [documentBlob, documentFileName, documentKey, isCtrlReady]);
+        openingDocumentKeyRef.current = null;
+        setIsBusy(false);
+      } catch {
+        openingDocumentKeyRef.current = null;
+        setIsBusy(false);
+      }
+    },
+    [documentKey, isCtrlReady],
+  );
 
   useEffect(() => {
     if (
@@ -117,8 +120,19 @@ function HangulGiangi({
     ) {
       return;
     }
-    handleOpen();
-  }, [documentKey, handleOpen, isCtrlReady]);
+    openHwpxBlob(documentBlob, documentFileName);
+  }, [documentBlob, documentFileName, documentKey, isCtrlReady, openHwpxBlob]);
+
+  const handleToolbarOpen = useCallback(
+    (file: File) => {
+      if (!file.name.toLowerCase().endsWith(".hwpx")) {
+        alert("HWPX 파일만 열 수 있습니다.");
+        return;
+      }
+      openHwpxBlob(file, file.name);
+    },
+    [openHwpxBlob],
+  );
 
   const handleSave = useCallback(() => {
     const ctrl = resolveHwpCtrl(iframeRef.current, isCtrlReady);
@@ -185,6 +199,7 @@ function HangulGiangi({
       <HangulGiangiToolbar
         isBusy={isBusy || !isCtrlReady}
         canSave={canSave}
+        onOpen={handleToolbarOpen}
         onSave={handleSave}
         onDownload={handleDownload}
         onFullscreen={handleFullscreen}