diff --git a/src/app/(admin)/admin/_components/AdminMenuSection/AdminMenuSection.tsx b/src/app/(admin)/admin/_components/AdminMenuSection/AdminMenuSection.tsx
index 293e681..bd0225d 100644
--- a/src/app/(admin)/admin/_components/AdminMenuSection/AdminMenuSection.tsx
+++ b/src/app/(admin)/admin/_components/AdminMenuSection/AdminMenuSection.tsx
@@ -1,5 +1,8 @@
+"use client";
+
 import { Fragment, ReactNode } from "react";
 import Link from "next/link";
+import { usePathname } from "next/navigation";
 import { Icon } from "@/components";
 import { ADMIN_NAV_SECTIONS } from "../../_constants/ADMIN_NAV_SECTIONS";
 import { AdminLogoutButton } from "../_internal";
@@ -36,16 +39,31 @@ interface AdminSectionNavItemProps {
 }
 
 const AdminSectionNavItem = ({ label, items, footer }: AdminSectionNavItemProps) => {
+  const pathname = usePathname();
+
+  const isCurrent = (href: string) =>
+    pathname !== null && (pathname === href || pathname.startsWith(`${href}/`));
+
   return (
-    <section aria-label={label} className="flex flex-col gap-[2px] px-5 py-6">
+    <section aria-label={label} className="flex flex-col gap-[2px] px-5 py-6 pc:py-4">
       <h2 className="text-body2-regular text-layout-body-default">{label}</h2>
 
       <ul>
         {items.map(({ href, title }) => (
           <li key={href}>
-            <Link href={href} className="flex items-center justify-between py-[10px]">
-              <span className="text-body1-semibold text-neutral-strong-default">{title}</span>
-              <Icon name="ArrowRightSmall" size={24} className="text-neutral-strong-default" />
+            <Link
+              href={href}
+              aria-current={isCurrent(href) ? "page" : undefined}
+              className="group flex items-center justify-between py-[10px] pc:-mx-3 pc:rounded-[10px] pc:px-3 pc:transition-colors pc:hover:bg-flatGray-25 pc:aria-[current=page]:bg-fill-brand-subtle-default"
+            >
+              <span className="text-body1-semibold text-neutral-strong-default pc:group-aria-[current=page]:text-brand-normal-default">
+                {title}
+              </span>
+              <Icon
+                name="ArrowRightSmall"
+                size={24}
+                className="text-neutral-strong-default pc:hidden"
+              />
             </Link>
           </li>
         ))}
diff --git a/src/app/(admin)/admin/_components/AdminProfile/AdminProfile.tsx b/src/app/(admin)/admin/_components/AdminProfile/AdminProfile.tsx
index f6be528..a6fa8fd 100644
--- a/src/app/(admin)/admin/_components/AdminProfile/AdminProfile.tsx
+++ b/src/app/(admin)/admin/_components/AdminProfile/AdminProfile.tsx
@@ -10,15 +10,31 @@ const AdminProfile = () => {
   const { email, nickname, profileImg } = data?.result || {};
 
   return (
-    <header className="flex items-center justify-between px-5 py-[30px]">
+    <header className="flex items-center justify-between px-5 py-[30px] pc:flex-col pc:items-stretch pc:gap-5">
       {isLoading ? (
         <SkeletonAdminProfile />
       ) : (
-        <div className="flex items-center gap-6">
-          <ProfileAvatar src={profileImg} alt={nickname} size={60} priority />
-          <div>
-            <p className="text-body1-semibold text-layout-header-default">{nickname}</p>
-            <span className="text-body2-regular text-layout-body-default">{email}</span>
+        <div className="flex items-center gap-6 pc:min-w-0 pc:gap-4">
+          <ProfileAvatar
+            src={profileImg}
+            alt={nickname}
+            size={60}
+            priority
+            className="pc:shrink-0"
+          />
+          <div className="pc:min-w-0">
+            <p
+              title={nickname}
+              className="text-body1-semibold text-layout-header-default pc:truncate"
+            >
+              {nickname}
+            </p>
+            <span
+              title={email}
+              className="text-body2-regular text-layout-body-default pc:block pc:truncate"
+            >
+              {email}
+            </span>
           </div>
         </div>
       )}
@@ -29,6 +45,7 @@ const AdminProfile = () => {
         aria-label="관리자 프로필 수정"
         variant="outlined"
         size="small"
+        className="pc:w-full"
       >
         프로필 수정
       </Button>
diff --git a/src/app/(admin)/admin/_components/AdminSidebar/AdminSidebar.tsx b/src/app/(admin)/admin/_components/AdminSidebar/AdminSidebar.tsx
new file mode 100644
index 0000000..8938c3e
--- /dev/null
+++ b/src/app/(admin)/admin/_components/AdminSidebar/AdminSidebar.tsx
@@ -0,0 +1,23 @@
+import AdminMenuSection from "../AdminMenuSection/AdminMenuSection";
+import AdminProfile from "../AdminProfile/AdminProfile";
+
+/**
+ * PC 화면에서 모든 관리자 화면 왼쪽에 고정되는 사이드바입니다.
+ *
+ * @remarks
+ * - PC 미만에서는 렌더만 하고 숨기며, 그 크기에서는 `/admin` 메인이 같은 프로필과 메뉴를 보여줍니다.
+ */
+
+const AdminSidebar = () => {
+  return (
+    <aside
+      aria-label="관리자 사이드바"
+      className="hidden pc:sticky pc:top-0 pc:flex pc:h-dvh pc:w-[320px] pc:shrink-0 pc:flex-col pc:overflow-y-auto pc:border-r pc:border-divider-default"
+    >
+      <AdminProfile />
+      <AdminMenuSection />
+    </aside>
+  );
+};
+
+export default AdminSidebar;
diff --git a/src/app/(admin)/admin/_components/_internal/SkeletonAdminProfile/SkeletonAdminProfile.tsx b/src/app/(admin)/admin/_components/_internal/SkeletonAdminProfile/SkeletonAdminProfile.tsx
index 2e71464..112b8fc 100644
--- a/src/app/(admin)/admin/_components/_internal/SkeletonAdminProfile/SkeletonAdminProfile.tsx
+++ b/src/app/(admin)/admin/_components/_internal/SkeletonAdminProfile/SkeletonAdminProfile.tsx
@@ -1,6 +1,6 @@
 const SkeletonAdminProfile = () => {
   return (
-    <div className="flex items-center gap-6">
+    <div className="flex items-center gap-6 pc:gap-4">
       <div className="skeleton-animation size-[60px] rounded-full" />
       <div className="flex flex-col gap-2">
         <div className="skeleton-animation h-5 w-[70px] rounded-full" />
diff --git a/src/app/(admin)/admin/_components/index.ts b/src/app/(admin)/admin/_components/index.ts
index 278188b..8c94030 100644
--- a/src/app/(admin)/admin/_components/index.ts
+++ b/src/app/(admin)/admin/_components/index.ts
@@ -6,3 +6,4 @@ export { default as AdminSearch } from "./AdminSearch/AdminSearch";
 export { default as AdminReportsItem } from "./AdminReportsItem/AdminReportsItem";
 export { default as AdminDetailSection } from "./AdminDetailSection/AdminDetailSection";
 export { default as AdminDropdown } from "./AdminDropdown/AdminDropdown";
+export { default as AdminSidebar } from "./AdminSidebar/AdminSidebar";
diff --git a/src/app/(admin)/admin/layout.tsx b/src/app/(admin)/admin/layout.tsx
index 1753f05..f8f7c3f 100644
--- a/src/app/(admin)/admin/layout.tsx
+++ b/src/app/(admin)/admin/layout.tsx
@@ -1,5 +1,6 @@
 import { ReactNode } from "react";
 import type { Metadata } from "next";
+import { AdminSidebar } from "./_components";
 
 export const metadata: Metadata = {
   title: {
@@ -34,7 +35,12 @@ export const metadata: Metadata = {
 };
 
 const layout = ({ children }: { children: ReactNode }) => {
-  return children;
+  return (
+    <div className="pc:flex">
+      <AdminSidebar />
+      <div className="pc:min-w-0 pc:flex-1">{children}</div>
+    </div>
+  );
 };
 
 export default layout;
diff --git a/src/app/(admin)/admin/notice/write/[id]/_components/NoticeEditForm/NoticeEditForm.tsx b/src/app/(admin)/admin/notice/write/[id]/_components/NoticeEditForm/NoticeEditForm.tsx
index 53d7836..c7b134e 100644
--- a/src/app/(admin)/admin/notice/write/[id]/_components/NoticeEditForm/NoticeEditForm.tsx
+++ b/src/app/(admin)/admin/notice/write/[id]/_components/NoticeEditForm/NoticeEditForm.tsx
@@ -36,7 +36,7 @@ const NoticeEditForm = ({ noticeId }: NoticeEditFormProps) => {
       <CategoryInput />
       <ContentInput />
       <NoticeEditImageSection helpText={IMAGE_HELP_TEXT} />
-      <div className="sticky bottom-0 w-full max-w-[764px] border-t border-divider-default bg-white">
+      <div className="sticky bottom-0 w-full max-w-[764px] border-t border-divider-default bg-white pc:max-w-none">
         <WriteActionSection disabled={isSubmitDisabled} />
       </div>
     </form>
diff --git a/src/app/(admin)/admin/notice/write/_components/NoticeWriteForm/NoticeWriteForm.tsx b/src/app/(admin)/admin/notice/write/_components/NoticeWriteForm/NoticeWriteForm.tsx
index 1360d3a..678ffe1 100644
--- a/src/app/(admin)/admin/notice/write/_components/NoticeWriteForm/NoticeWriteForm.tsx
+++ b/src/app/(admin)/admin/notice/write/_components/NoticeWriteForm/NoticeWriteForm.tsx
@@ -24,7 +24,7 @@ const NoticeWriteForm = ({ methods }: { methods: UseFormReturn<NoticeWriteFormVa
       <CategoryInput />
       <ContentInput />
       <WriteImageSection helpText={IMAGE_HELP_TEXT} />
-      <div className="sticky bottom-0 w-full max-w-[764px] border-t border-divider-default bg-white">
+      <div className="sticky bottom-0 w-full max-w-[764px] border-t border-divider-default bg-white pc:max-w-none">
         <WriteActionSection disabled={isSubmitDisabled} />
       </div>
     </form>
diff --git a/src/app/(admin)/admin/page.tsx b/src/app/(admin)/admin/page.tsx
index 426b7dc..0068069 100644
--- a/src/app/(admin)/admin/page.tsx
+++ b/src/app/(admin)/admin/page.tsx
@@ -10,8 +10,14 @@ const page = async () => {
     <div className="h-base">
       <h1 className="sr-only">관리자 페이지</h1>
 
-      <AdminProfile />
-      <AdminMenuSection />
+      <div className="pc:hidden">
+        <AdminProfile />
+        <AdminMenuSection />
+      </div>
+
+      <p className="hidden py-[160px] text-body1-regular text-layout-body-default pc:flex-center">
+        왼쪽 메뉴에서 관리할 항목을 선택해 주세요.
+      </p>
     </div>
   );
 };
diff --git a/src/app/(auth)/login/_components/AdminLoginForm/AdminLoginForm.tsx b/src/app/(auth)/login/_components/AdminLoginForm/AdminLoginForm.tsx
index 0302079..ed83192 100644
--- a/src/app/(auth)/login/_components/AdminLoginForm/AdminLoginForm.tsx
+++ b/src/app/(auth)/login/_components/AdminLoginForm/AdminLoginForm.tsx
@@ -39,7 +39,7 @@ const AdminLoginForm = () => {
 
   return (
     <form onSubmit={onSubmitLogin}>
-      <div className="flex min-h-dvh w-full gap-12 px-4 py-[64px] flex-col-center tablet:px-[80px]">
+      <div className="flex min-h-dvh w-full gap-12 px-4 py-[64px] flex-col-center tablet:px-[80px] pc:mx-auto pc:max-w-[480px] pc:px-0">
         <div className="flex w-full flex-col items-center gap-10">
           <Icon name="Logo" size={120} title="찾아줘! 관리자" />
 
diff --git a/src/app/layout.tsx b/src/app/layout.tsx
index 9e6c235..e249020 100644
--- a/src/app/layout.tsx
+++ b/src/app/layout.tsx
@@ -68,7 +68,7 @@ export default function RootLayout({
 
   return (
     <html lang="ko" className={pretendard.variable}>
-      <body className="mx-auto max-w-[768px] border-x-2 flex-col-center">
+      <body className="mx-auto max-w-[768px] border-x-2 flex-col-center pc:max-w-none pc:border-x-0">
         <AppProviders>
           <main className="w-full flex-1">{children}</main>
         </AppProviders>
diff --git a/src/components/layout/DetailHeader/DetailHeader.tsx b/src/components/layout/DetailHeader/DetailHeader.tsx
index be1e461..8f507ba 100644
--- a/src/components/layout/DetailHeader/DetailHeader.tsx
+++ b/src/components/layout/DetailHeader/DetailHeader.tsx
@@ -12,6 +12,7 @@ import { cn } from "@/utils";
  * - `"use client"`이며 `next/navigation`의 `useRouter`로 뒤로가기 동작을 처리합니다.
  * - `onBack`이 있으면 뒤로 버튼은 그만 호출하고, 없으면 `sessionStorage`의 `__fmi_history_count`를 보고 `router.back()` 또는 `/`로 이동합니다.
  * - `fixed` 헤더 아래 콘텐츠가 가리지 않도록 동일 높이의 자리 표시 `div`를 둡니다.
+ * - PC에서는 사이드바 옆 본문 폭을 따라가도록 `sticky`로 바뀌고 자리 표시 `div`는 숨깁니다.
  * - 오른쪽 액션은 `DetailHeaderParts`(저장, 검색, 즐겨찾기, 메뉴 등)를 `children`으로 넣는 패턴을 씁니다.
  *
  * @author hyungjun
@@ -81,6 +82,7 @@ const DetailHeader = ({ title = "", children, onBack, onBeforeBack }: DetailHead
       <header
         className={cn(
           "fixed top-0 z-30 mx-auto flex w-full max-w-[764px] items-center justify-between bg-white px-5 pt-[var(--safe-area-top)]",
+          "pc:sticky pc:max-w-none pc:border-b pc:border-divider-default",
           HEADER_HEIGHT
         )}
       >
@@ -101,7 +103,7 @@ const DetailHeader = ({ title = "", children, onBack, onBeforeBack }: DetailHead
           </div>
         )}
       </header>
-      <div className={HEADER_HEIGHT} aria-hidden />
+      <div className={cn(HEADER_HEIGHT, "pc:hidden")} aria-hidden />
     </>
   );
 };