diff --git a/.changeset/sunny-titles-resolve.md b/.changeset/sunny-titles-resolve.md
new file mode 100644
index 000000000..315d1416c
--- /dev/null
+++ b/.changeset/sunny-titles-resolve.md
@@ -0,0 +1,5 @@
+---
+"@tailor-platform/app-shell": patch
+---
+
+Fix `SidebarItem` title overrides accepting localized strings. Pass a value from `defineI18nLabels` directly to `title` and it resolves with the active AppShell locale.
diff --git a/docs-manifest.json b/docs-manifest.json
index 718997a22..70509a247 100644
--- a/docs-manifest.json
+++ b/docs-manifest.json
@@ -1147,10 +1147,10 @@
       "claims": [],
       "symbols": ["SidebarItem", "SidebarItemProps"],
       "hashes": {
-        "typeSurface": "7be21739c231ede3",
-        "outline": "1cc674b956d09fab",
+        "typeSurface": "37530cafa374d799",
+        "outline": "d1bbcfac50071047",
         "snapshot": null,
-        "outputMd": "d55d38352040ef2c",
+        "outputMd": "9236c03e53aa79f2",
         "examples": null
       }
     },
@@ -1182,9 +1182,9 @@
       "symbols": [],
       "hashes": {
         "typeSurface": null,
-        "outline": "74f353988f15c82b",
+        "outline": "91f0fa065f3a3192",
         "snapshot": null,
-        "outputMd": "96f1cf893c231861",
+        "outputMd": "dc6b3afc049b4148",
         "examples": null
       }
     },
@@ -1587,7 +1587,7 @@
     "packages/core/skills/app-shell-patterns/references/concepts/graphql.md": "ba5107604e4f42e8",
     "packages/core/skills/app-shell-patterns/references/concepts/modules-and-resources.md": "bf15b5460f22d165",
     "packages/core/skills/app-shell-patterns/references/concepts/routing-navigation.md": "2f3ff3f095c2b1cc",
-    "packages/core/skills/app-shell-patterns/references/concepts/sidebar-navigation.md": "96f1cf893c231861",
+    "packages/core/skills/app-shell-patterns/references/concepts/sidebar-navigation.md": "dc6b3afc049b4148",
     "packages/core/skills/app-shell-patterns/references/concepts/styling-theming.md": "0133fdae405f467c",
     "packages/core/skills/app-shell-patterns/references/components/action-panel.md": "71794d4b561e4d4b",
     "packages/core/skills/app-shell-patterns/references/components/activity-card.md": "4f386e49380fb0b0",
@@ -1622,7 +1622,7 @@
     "packages/core/skills/app-shell-patterns/references/components/select.md": "ae287e2bb5abc1c6",
     "packages/core/skills/app-shell-patterns/references/components/sheet.md": "1f81ebd562c50371",
     "packages/core/skills/app-shell-patterns/references/components/sidebar-group.md": "7288fdf8bb5c19b9",
-    "packages/core/skills/app-shell-patterns/references/components/sidebar-item.md": "d55d38352040ef2c",
+    "packages/core/skills/app-shell-patterns/references/components/sidebar-item.md": "9236c03e53aa79f2",
     "packages/core/skills/app-shell-patterns/references/components/sidebar-layout.md": "e50b2d649289d772",
     "packages/core/skills/app-shell-patterns/references/components/spinner.md": "e05d94ba9c3d17da",
     "packages/core/skills/app-shell-patterns/references/components/table.md": "f85ec64ceb7f4acf",
diff --git a/docs-src/components/sidebar-item.docs.outline.md b/docs-src/components/sidebar-item.docs.outline.md
index 3abc60271..9823d083d 100644
--- a/docs-src/components/sidebar-item.docs.outline.md
+++ b/docs-src/components/sidebar-item.docs.outline.md
@@ -9,7 +9,7 @@ sources:
 
 # SidebarItem
 
-`SidebarItem` represents an individual navigation link in the sidebar. It automatically resolves titles and icons from resource definitions and provides active state highlighting.
+`SidebarItem` represents an individual navigation link in the sidebar. It automatically resolves titles and icons from resource definitions, supports localized title overrides, and provides active state highlighting.
 
 ## Import
 
@@ -36,7 +36,7 @@ When you only provide `to`, the title and icon are automatically resolved from t
 | Prop          | Type                   | Default       | Description                                    |
 | ------------- | ---------------------- | ------------- | ---------------------------------------------- |
 | `to`          | `string`               | **Required**  | Target URL (internal or external)              |
-| `title`       | `string`               | Auto-resolved | Override the display title                     |
+| `title`       | `LocalizedString`      | Auto-resolved | Override the display title (i18n supported)    |
 | `icon`        | `React.ReactNode`      | Auto-resolved | Override the icon                              |
 | `external`    | `boolean`              | `false`       | Opens link in new tab with external icon       |
 | `activeMatch` | `"exact" \| "prefix"`  | `"prefix"`    | How to match the current path for active state |
@@ -106,6 +106,14 @@ const modules = [
 />
 ```
 
+### Localized Override
+
+Pass a `LocalizedString`, such as a value from `defineI18nLabels`, to resolve the override using the current AppShell locale:
+
+```tsx
+<SidebarItem to="/dashboard" title={labels.t("dashboard")} />
+```
+
 ### Override Icon
 
 ```tsx
diff --git a/docs-src/concepts/sidebar-navigation.docs.outline.md b/docs-src/concepts/sidebar-navigation.docs.outline.md
index c8020c22d..853d9eace 100644
--- a/docs-src/concepts/sidebar-navigation.docs.outline.md
+++ b/docs-src/concepts/sidebar-navigation.docs.outline.md
@@ -72,13 +72,13 @@ A navigation item that automatically resolves title and icon from resource defin
 
 #### Props
 
-| Prop       | Type        | Required | Description                                                           |
-| ---------- | ----------- | -------- | --------------------------------------------------------------------- |
-| `to`       | `string`    | Yes      | Target URL. External URLs (http://...) are rendered as external links |
-| `title`    | `string`    | No       | Override title. When omitted, auto-resolved from resource meta        |
-| `icon`     | `ReactNode` | No       | Override icon. When omitted, auto-resolved from resource meta         |
-| `external` | `boolean`   | No       | Opens link in new tab with external link icon                         |
-| `render`   | `function`  | No       | Custom render function for full UI control                            |
+| Prop       | Type              | Required | Description                                                                     |
+| ---------- | ----------------- | -------- | ------------------------------------------------------------------------------- |
+| `to`       | `string`          | Yes      | Target URL. External URLs (http://...) are rendered as external links           |
+| `title`    | `LocalizedString` | No       | Override title (i18n supported). When omitted, auto-resolved from resource meta |
+| `icon`     | `ReactNode`       | No       | Override icon. When omitted, auto-resolved from resource meta                   |
+| `external` | `boolean`         | No       | Opens link in new tab with external link icon                                   |
+| `render`   | `function`        | No       | Custom render function for full UI control                                      |
 
 #### Examples
 
diff --git a/docs/components/sidebar-item.md b/docs/components/sidebar-item.md
index be600e416..160b757b1 100644
--- a/docs/components/sidebar-item.md
+++ b/docs/components/sidebar-item.md
@@ -7,7 +7,7 @@ description: Individual navigation item for customizing sidebar with icons, acti
 
 # SidebarItem
 
-`SidebarItem` represents an individual navigation link in the sidebar. It automatically resolves titles and icons from resource definitions and provides active state highlighting.
+`SidebarItem` represents an individual navigation link in the sidebar. It automatically resolves titles and icons from resource definitions, supports localized title overrides, and provides active state highlighting.
 
 ## Import
 
@@ -34,7 +34,7 @@ When you only provide `to`, the title and icon are automatically resolved from t
 | Prop          | Type                   | Default       | Description                                    |
 | ------------- | ---------------------- | ------------- | ---------------------------------------------- |
 | `to`          | `string`               | **Required**  | Target URL (internal or external)              |
-| `title`       | `string`               | Auto-resolved | Override the display title                     |
+| `title`       | `LocalizedString`      | Auto-resolved | Override the display title (i18n supported)    |
 | `icon`        | `React.ReactNode`      | Auto-resolved | Override the icon                              |
 | `external`    | `boolean`              | `false`       | Opens link in new tab with external icon       |
 | `activeMatch` | `"exact" \| "prefix"`  | `"prefix"`    | How to match the current path for active state |
@@ -104,6 +104,14 @@ const modules = [
 />
 ```
 
+### Localized Override
+
+Pass a `LocalizedString`, such as a value from `defineI18nLabels`, to resolve the override using the current AppShell locale:
+
+```tsx
+<SidebarItem to="/dashboard" title={labels.t("dashboard")} />
+```
+
 ### Override Icon
 
 ```tsx
diff --git a/docs/concepts/sidebar-navigation.md b/docs/concepts/sidebar-navigation.md
index 843f937fb..4c3924431 100644
--- a/docs/concepts/sidebar-navigation.md
+++ b/docs/concepts/sidebar-navigation.md
@@ -72,13 +72,13 @@ A navigation item that automatically resolves title and icon from resource defin
 
 #### Props
 
-| Prop       | Type        | Required | Description                                                           |
-| ---------- | ----------- | -------- | --------------------------------------------------------------------- |
-| `to`       | `string`    | Yes      | Target URL. External URLs (http://...) are rendered as external links |
-| `title`    | `string`    | No       | Override title. When omitted, auto-resolved from resource meta        |
-| `icon`     | `ReactNode` | No       | Override icon. When omitted, auto-resolved from resource meta         |
-| `external` | `boolean`   | No       | Opens link in new tab with external link icon                         |
-| `render`   | `function`  | No       | Custom render function for full UI control                            |
+| Prop       | Type              | Required | Description                                                                     |
+| ---------- | ----------------- | -------- | ------------------------------------------------------------------------------- |
+| `to`       | `string`          | Yes      | Target URL. External URLs (http://...) are rendered as external links           |
+| `title`    | `LocalizedString` | No       | Override title (i18n supported). When omitted, auto-resolved from resource meta |
+| `icon`     | `ReactNode`       | No       | Override icon. When omitted, auto-resolved from resource meta                   |
+| `external` | `boolean`         | No       | Opens link in new tab with external link icon                                   |
+| `render`   | `function`        | No       | Custom render function for full UI control                                      |
 
 #### Examples
 
diff --git a/packages/core/src/components/sidebar/sidebar-item.tsx b/packages/core/src/components/sidebar/sidebar-item.tsx
index f8edaf9a5..2fb641b29 100644
--- a/packages/core/src/components/sidebar/sidebar-item.tsx
+++ b/packages/core/src/components/sidebar/sidebar-item.tsx
@@ -3,6 +3,8 @@ import { useLocation, Link } from "react-router";
 import { ExternalLink } from "lucide-react";
 import { SidebarMenuItem, SidebarMenuButton } from "./primitives";
 import { usePageMeta } from "@/hooks/use-page-meta";
+import { useAppShellConfig } from "@/contexts/appshell-context";
+import { buildLocaleResolver, type LocalizedString } from "@/lib/i18n";
 
 export type SidebarItemRenderProps = {
   /** Title auto-resolved from resource meta */
@@ -23,10 +25,10 @@ export type SidebarItemProps = {
   to: string;
 
   /**
-   * Override title.
+   * Override title (i18n supported).
    * When omitted, title is auto-resolved from resource meta.
    */
-  title?: string;
+  title?: LocalizedString;
 
   /**
    * Override icon.
@@ -96,13 +98,19 @@ export const SidebarItem = (props: SidebarItemProps) => {
     icon: iconOverride,
   } = props;
   const { pathname: currentPath } = useLocation();
+  const { configurations } = useAppShellConfig();
   const pageMeta = usePageMeta(to);
+  const resolve = buildLocaleResolver(configurations.locale);
 
   const isActive =
     activeMatch === "exact"
       ? currentPath === to
       : currentPath === to || currentPath.startsWith(`${to}/`);
-  const title = titleOverride ?? pageMeta?.title ?? extractTitleFromUrl(to);
+  const fallbackTitle = pageMeta?.title ?? extractTitleFromUrl(to);
+  const title =
+    typeof titleOverride === "function"
+      ? resolve(titleOverride, fallbackTitle)
+      : (titleOverride ?? fallbackTitle);
   const icon = iconOverride ?? pageMeta?.icon;
 
   const renderProps: SidebarItemRenderProps = {
diff --git a/packages/core/src/components/sidebar/sidebar.test.tsx b/packages/core/src/components/sidebar/sidebar.test.tsx
index bb495e437..b0d5f6a60 100644
--- a/packages/core/src/components/sidebar/sidebar.test.tsx
+++ b/packages/core/src/components/sidebar/sidebar.test.tsx
@@ -90,11 +90,15 @@ const testConfig: RootConfiguration = {
 /**
  * Wrapper to render sidebar components with all required providers.
  */
-const renderWithProviders = (ui: React.ReactNode, initialPath = "/dashboard/overview") => {
+const renderWithProviders = (
+  ui: React.ReactNode,
+  initialPath = "/dashboard/overview",
+  locale = "en",
+) => {
   stubDesktopViewport();
   return render(
     <MemoryRouter initialEntries={[initialPath]}>
-      <AppShellConfigContext.Provider value={{ configurations: testConfig }}>
+      <AppShellConfigContext.Provider value={{ configurations: { ...testConfig, locale } }}>
         <SidebarProvider>
           <SidebarMenu data-testid="sidebar-menu">{ui}</SidebarMenu>
         </SidebarProvider>
@@ -118,6 +122,18 @@ describe("SidebarItem", () => {
     expect(menu.getByRole("link", { name: /dashboard/i })).toBeDefined();
   });
 
+  it("resolves localized title overrides", () => {
+    renderWithProviders(<SidebarItem to="/dashboard" title={localizedTitle} />, undefined, "ja");
+
+    expect(getSidebarMenu().getByRole("link", { name: "製品" })).toBeDefined();
+  });
+
+  it("preserves empty string title overrides", () => {
+    renderWithProviders(<SidebarItem to="/dashboard" title="" />);
+
+    expect(getSidebarMenu().getByRole("link").textContent).toBe("");
+  });
+
   it("renders with custom render function", () => {
     renderWithProviders(
       <SidebarItem