diff --git a/packages/common/components/src/ui/header/index.tsx b/packages/common/components/src/ui/header/index.tsx
index 5ff9699e4..8b8bb5e3c 100644
--- a/packages/common/components/src/ui/header/index.tsx
+++ b/packages/common/components/src/ui/header/index.tsx
@@ -136,11 +136,14 @@ export function Header({
   authService,
   tokenManager,
   viewOnly,
+  showSidebarTrigger = true,
 }: {
   authService?: AuthService;
   /** @deprecated authService를 사용하세요. */
   tokenManager?: TokenManager;
   viewOnly?: boolean;
+  /** false 이면 LNB 토글 버튼을 헤더에 렌더링하지 않고 같은 크기의 자리만 유지 (BaseLayout 이 LNB 바로 앞에 렌더링) */
+  showSidebarTrigger?: boolean;
 }) {
   const [mounted, setMounted] = useState(false);
   const [logoWidth, setLogoWidth] = useState(0);
@@ -276,7 +279,11 @@ export function Header({
     >
       <div className="flex w-full items-center justify-between px-2 sm:w-auto sm:justify-start sm:px-4 md:px-6">
         <div className="flex items-center gap-2 sm:gap-4">
-          <SidebarTrigger className="size-12 !bg-transparent p-2 hover:!bg-accent [&>svg]:!size-full [&>svg]:text-foreground" />
+          {showSidebarTrigger ? (
+            <SidebarTrigger className="size-12 !bg-transparent p-2 hover:!bg-accent [&>svg]:!size-full [&>svg]:text-foreground" />
+          ) : (
+            <span aria-hidden="true" className="size-12 shrink-0" />
+          )}
           <h1>
             {/* 로고·사이트명 클릭 시 메인으로 이동 */}
             <a
diff --git a/packages/common/components/src/ui/layout/base.tsx b/packages/common/components/src/ui/layout/base.tsx
index fd10d559e..84e65b864 100644
--- a/packages/common/components/src/ui/layout/base.tsx
+++ b/packages/common/components/src/ui/layout/base.tsx
@@ -3,7 +3,7 @@ import type { QueryClient } from "@tanstack/react-query";
 import { QueryProvider } from "../../provider/query-provider";
 import { PopupProvider } from "../../provider/popup-provider";
 import type { MenuItem } from "../../api";
-import { SidebarProvider } from "../sidebar";
+import { SidebarProvider, SidebarTrigger } from "../sidebar";
 import { LNB } from "../lnb";
 import { Header } from "../header";
 import { Footer } from "../footer";
@@ -17,6 +17,7 @@ export function BaseLayout({
   tokenManager,
   currentPath,
   handleMenuClick,
+  sidebarTriggerPlacement = "header",
 }: {
   children: React.ReactNode;
   queryClient?: QueryClient;
@@ -25,7 +26,15 @@ export function BaseLayout({
   tokenManager?: TokenManager;
   currentPath?: string;
   handleMenuClick?: (item: MenuItem) => void;
+  /**
+   * LNB 토글 버튼의 DOM 위치.
+   * - "header": 헤더 로고(h1) 앞 (기존)
+   * - "lnb": LNB 바로 앞 (콘텐츠 선형 구조 준수). 화면 위치는 CSS 로 헤더 좌측에 동일하게 유지
+   */
+  sidebarTriggerPlacement?: "header" | "lnb";
 }) {
+  const isTriggerBeforeLnb = sidebarTriggerPlacement === "lnb";
+
   return (
     <QueryProvider queryClient={queryClient}>
       <PopupProvider>
@@ -35,7 +44,15 @@ export function BaseLayout({
             <Header
               authService={authService}
               tokenManager={authService ? undefined : tokenManager}
+              showSidebarTrigger={!isTriggerBeforeLnb}
             />
+            {/* 접기/펼치기 버튼을 제어 대상(LNB) 바로 앞에 배치하고, 화면에서는 헤더 좌측(기존 위치)에 고정 */}
+            {isTriggerBeforeLnb && (
+              <SidebarTrigger
+                aria-controls="lnb"
+                className="fixed left-2 top-0 z-40 size-12 !bg-transparent p-2 hover:!bg-accent [&>svg]:!size-full [&>svg]:text-foreground sm:left-4 sm:top-[1.5rem] md:left-6"
+              />
+            )}
             <div className="flex">
               <LNB
                 currentPath={currentPath}