diff --git a/packages/menu-bar/src/vaadin-menu-bar-mixin.d.ts b/packages/menu-bar/src/vaadin-menu-bar-mixin.d.ts
index a870609c436..65ad1dfc318 100644
--- a/packages/menu-bar/src/vaadin-menu-bar-mixin.d.ts
+++ b/packages/menu-bar/src/vaadin-menu-bar-mixin.d.ts
@@ -11,7 +11,7 @@ import type { KeyboardMixinClass } from '@vaadin/a11y-base/src/keyboard-mixin.js
 import type { ControllerMixinClass } from '@vaadin/component-base/src/controller-mixin.js';
 import type { ResizeMixinClass } from '@vaadin/component-base/src/resize-mixin.js';
 
-export interface MenuBarItem {
+export type MenuBarItem<TItemData extends object = object> = {
   /**
    * Text to be set as the menu button component's textContent.
    */
@@ -37,40 +37,40 @@ export interface MenuBarItem {
   /**
    * Array of submenu items.
    */
-  children?: SubMenuItem[];
+  children?: Array<SubMenuItem<TItemData>>;
 
   /**
    * Class/classes to be set to the class attribute of the button.
    */
   className?: string;
-}
+} & TItemData;
 
-export interface SubMenuItem {
+export type SubMenuItem<TItemData extends object = object> = {
   text?: string;
   component?: HTMLElement | string;
   disabled?: boolean;
   theme?: string[] | string;
   checked?: boolean;
   className?: string;
-  children?: SubMenuItem[];
-}
+  children?: Array<SubMenuItem<TItemData>>;
+} & TItemData;
 
 export interface MenuBarI18n {
   moreOptions: string;
 }
 
-export declare function MenuBarMixin<T extends Constructor<HTMLElement>>(
+export declare function MenuBarMixin<T extends Constructor<HTMLElement>, TItem extends MenuBarItem = MenuBarItem>(
   base: T,
 ): Constructor<ControllerMixinClass> &
   Constructor<DisabledMixinClass> &
   Constructor<FocusMixinClass> &
   Constructor<KeyboardDirectionMixinClass> &
   Constructor<KeyboardMixinClass> &
-  Constructor<MenuBarMixinClass> &
+  Constructor<MenuBarMixinClass<TItem>> &
   Constructor<ResizeMixinClass> &
   T;
 
-export declare class MenuBarMixinClass {
+export declare class MenuBarMixinClass<TItem extends MenuBarItem = MenuBarItem> {
   /**
    * Defines a hierarchical structure, where root level items represent menu bar buttons,
    * and `children` property configures a submenu with items to be opened below
@@ -118,7 +118,7 @@ export declare class MenuBarMixinClass {
    * window.Vaadin.featureFlags.accessibleDisabledButtons = true;
    * ```
    */
-  items: MenuBarItem[];
+  items: TItem[];
 
   /**
    * The object used to localize this component.
@@ -183,3 +183,11 @@ export declare class MenuBarMixinClass {
 
   protected _hasOverflow: boolean;
 }
+
+export declare interface MenuBarMixinClass
+  extends ControllerMixinClass,
+    DisabledMixinClass,
+    FocusMixinClass,
+    KeyboardDirectionMixinClass,
+    KeyboardMixinClass,
+    ResizeMixinClass {}
diff --git a/packages/menu-bar/src/vaadin-menu-bar.d.ts b/packages/menu-bar/src/vaadin-menu-bar.d.ts
index fad4cfd6b94..7137aa1a38e 100644
--- a/packages/menu-bar/src/vaadin-menu-bar.d.ts
+++ b/packages/menu-bar/src/vaadin-menu-bar.d.ts
@@ -3,23 +3,25 @@
  * Copyright (c) 2019 - 2025 Vaadin Ltd.
  * This program is available under Apache License Version 2.0, available at https://vaadin.com/license/
  */
-import { DisabledMixin } from '@vaadin/a11y-base/src/disabled-mixin.js';
-import { ElementMixin } from '@vaadin/component-base/src/element-mixin.js';
-import { ThemableMixin } from '@vaadin/vaadin-themable-mixin/vaadin-themable-mixin.js';
-import { type MenuBarItem, MenuBarMixin } from './vaadin-menu-bar-mixin.js';
+import type { DisabledMixinClass } from '@vaadin/a11y-base/src/disabled-mixin.js';
+import type { ElementMixinClass } from '@vaadin/component-base/src/element-mixin.js';
+import type { ThemableMixinClass } from '@vaadin/vaadin-themable-mixin/vaadin-themable-mixin.js';
+import type { MenuBarItem, MenuBarMixinClass } from './vaadin-menu-bar-mixin.js';
 
 export { MenuBarItem, MenuBarI18n, SubMenuItem } from './vaadin-menu-bar-mixin.js';
 
 /**
  * Fired when a submenu item or menu bar button without children is clicked.
  */
-export type MenuBarItemSelectedEvent = CustomEvent<{ value: MenuBarItem }>;
+export type MenuBarItemSelectedEvent<TItem extends MenuBarItem = MenuBarItem> = CustomEvent<{ value: TItem }>;
 
-export interface MenuBarCustomEventMap {
-  'item-selected': MenuBarItemSelectedEvent;
+export interface MenuBarCustomEventMap<TItem extends MenuBarItem = MenuBarItem> {
+  'item-selected': MenuBarItemSelectedEvent<TItem>;
 }
 
-export interface MenuBarEventMap extends HTMLElementEventMap, MenuBarCustomEventMap {}
+export interface MenuBarEventMap<TItem extends MenuBarItem = MenuBarItem>
+  extends HTMLElementEventMap,
+    MenuBarCustomEventMap<TItem> {}
 
 /**
  * `<vaadin-menu-bar>` is a Web Component providing a set of horizontally stacked buttons offering
@@ -77,20 +79,26 @@ export interface MenuBarEventMap extends HTMLElementEventMap, MenuBarCustomEvent
  *
  * @fires {CustomEvent} item-selected - Fired when a submenu item or menu bar button without children is clicked.
  */
-declare class MenuBar extends MenuBarMixin(DisabledMixin(ElementMixin(ThemableMixin(HTMLElement)))) {
-  addEventListener<K extends keyof MenuBarEventMap>(
+declare class MenuBar<TItem extends MenuBarItem = MenuBarItem> extends HTMLElement {
+  addEventListener<K extends keyof MenuBarEventMap<TItem>>(
     type: K,
-    listener: (this: MenuBar, ev: MenuBarEventMap[K]) => void,
+    listener: (this: MenuBar<TItem>, ev: MenuBarEventMap<TItem>[K]) => void,
     options?: AddEventListenerOptions | boolean,
   ): void;
 
-  removeEventListener<K extends keyof MenuBarEventMap>(
+  removeEventListener<K extends keyof MenuBarEventMap<TItem>>(
     type: K,
-    listener: (this: MenuBar, ev: MenuBarEventMap[K]) => void,
+    listener: (this: MenuBar<TItem>, ev: MenuBarEventMap<TItem>[K]) => void,
     options?: EventListenerOptions | boolean,
   ): void;
 }
 
+interface MenuBar<TItem extends MenuBarItem = MenuBarItem>
+  extends MenuBarMixinClass<TItem>,
+    DisabledMixinClass,
+    ElementMixinClass,
+    ThemableMixinClass {}
+
 declare global {
   interface HTMLElementTagNameMap {
     'vaadin-menu-bar': MenuBar;
diff --git a/packages/menu-bar/test/typings/menu-bar.types.ts b/packages/menu-bar/test/typings/menu-bar.types.ts
index 07e8f4aca73..d4969966988 100644
--- a/packages/menu-bar/test/typings/menu-bar.types.ts
+++ b/packages/menu-bar/test/typings/menu-bar.types.ts
@@ -9,7 +9,7 @@ import type { ThemableMixinClass } from '@vaadin/vaadin-themable-mixin/vaadin-th
 import type { MenuBarItem } from '../../src/vaadin-menu-bar-item.js';
 import type { MenuBarListBox } from '../../src/vaadin-menu-bar-list-box.js';
 import type { MenuBarMixinClass } from '../../src/vaadin-menu-bar-mixin.js';
-import type { MenuBarItem as MenuItem, MenuBarItemSelectedEvent } from '../../vaadin-menu-bar.js';
+import type { MenuBar, MenuBarItem as MenuItem, MenuBarItemSelectedEvent } from '../../vaadin-menu-bar.js';
 
 const menu = document.createElement('vaadin-menu-bar');
 
@@ -39,6 +39,22 @@ assertType<string[] | string | undefined>(menuItem.theme);
 assertType<MenuItem[] | undefined>(menuItem.children);
 assertType<HTMLElement | string | undefined>(menuItem.component);
 
+// Custom item data
+interface ItemData {
+  type: 'copy' | 'cut' | 'paste';
+  value: string;
+}
+
+const narrowedMenu = menu as MenuBar<MenuItem<ItemData>>;
+
+assertType<ItemData>(narrowedMenu.items[0]);
+assertType<ItemData>(narrowedMenu.items[0].children![0]);
+assertType<ItemData>(narrowedMenu.items[0].children![0].children![0]);
+
+narrowedMenu.addEventListener('item-selected', (event) => {
+  assertType<ItemData>(event.detail.value);
+});
+
 // Item
 const item = document.createElement('vaadin-menu-bar-item');