diff --git a/apps/desktop/main/index.ts b/apps/desktop/main/index.ts
index e55b9d66..1e6701f6 100644
--- a/apps/desktop/main/index.ts
+++ b/apps/desktop/main/index.ts
@@ -22,7 +22,11 @@ import {
 import { migrateAllDatabases, checkMigrationNeeded } from './database/core'
 import { initLocale } from './i18n'
 import { MigrationRunner, ALL_MIGRATIONS } from '@openchatlab/config'
-import { applyCurrentTitleBarOverlay, getTitleBarOverlayOptions } from './window-titlebar'
+import {
+  applyCurrentTitleBarOverlay,
+  getTitleBarOverlayOptions,
+  resetCurrentTitleBarOverlayColor,
+} from './window-titlebar'
 
 type AppWithQuitFlag = typeof app & { isQuiting?: boolean }
 // 统一通过扩展类型访问退出标记，避免使用 @ts-ignore。
@@ -243,6 +247,7 @@ class MainProcess {
         // 监听主题变化，动态更新颜色
         nativeTheme.on('updated', () => {
           if (this.mainWindow && platform.isWindows) {
+            resetCurrentTitleBarOverlayColor()
             applyCurrentTitleBarOverlay(this.mainWindow, nativeTheme.shouldUseDarkColors)
           }
         })
diff --git a/apps/desktop/main/ipc/window.ts b/apps/desktop/main/ipc/window.ts
index 9ed2e4c4..a32a2686 100644
--- a/apps/desktop/main/ipc/window.ts
+++ b/apps/desktop/main/ipc/window.ts
@@ -7,7 +7,11 @@ import * as fs from 'fs/promises'
 import type { IpcContext } from './types'
 import { simulateUpdateDialog, manualCheckForUpdates } from '../update'
 import { t } from '../i18n'
-import { applyCurrentTitleBarOverlay, applyTitleBarOverlayColor } from '../window-titlebar'
+import {
+  applyCurrentTitleBarOverlay,
+  applyTitleBarOverlayColor,
+  resetCurrentTitleBarOverlayColor,
+} from '../window-titlebar'
 
 type AppWithQuitFlag = typeof app & { isQuiting?: boolean }
 // 通过类型扩展记录应用退出意图，避免使用 @ts-ignore。
@@ -88,6 +92,7 @@ export function registerWindowHandlers(ctx: IpcContext): void {
 
     // Windows 上动态更新 overlay 颜色以匹配主题
     if (process.platform === 'win32' && win) {
+      resetCurrentTitleBarOverlayColor()
       applyCurrentTitleBarOverlay(win, nativeTheme.shouldUseDarkColors)
     }
   })
diff --git a/apps/desktop/main/window-titlebar.test.ts b/apps/desktop/main/window-titlebar.test.ts
index 4f873fab..32f8989f 100644
--- a/apps/desktop/main/window-titlebar.test.ts
+++ b/apps/desktop/main/window-titlebar.test.ts
@@ -1,6 +1,13 @@
 import assert from 'node:assert/strict'
 import { describe, it } from 'node:test'
-import { getTitleBarOverlayOptionsForColor, getTitleBarOverlayOptions } from './window-titlebar'
+import type { BrowserWindow, TitleBarOverlayOptions } from 'electron'
+import {
+  applyCurrentTitleBarOverlay,
+  applyTitleBarOverlayColor,
+  getTitleBarOverlayOptionsForColor,
+  getTitleBarOverlayOptions,
+  resetCurrentTitleBarOverlayColor,
+} from './window-titlebar'
 
 describe('Windows title bar overlay options', () => {
   it('keeps the native overlay background transparent in normal mode', () => {
@@ -28,4 +35,23 @@ describe('Windows title bar overlay options', () => {
       height: 32,
     })
   })
+
+  it('can drop a sampled color when the effective theme changes', () => {
+    const calls: TitleBarOverlayOptions[] = []
+    const win = {
+      setTitleBarOverlay: (options: TitleBarOverlayOptions) => {
+        calls.push(options)
+      },
+    } as Pick<BrowserWindow, 'setTitleBarOverlay'> as BrowserWindow
+
+    applyTitleBarOverlayColor(win, '#111827')
+    resetCurrentTitleBarOverlayColor()
+    applyCurrentTitleBarOverlay(win, false)
+
+    assert.deepEqual(calls.at(-1), {
+      color: 'rgba(0, 0, 0, 0)',
+      symbolColor: '#52525b',
+      height: 32,
+    })
+  })
 })
diff --git a/apps/desktop/main/window-titlebar.ts b/apps/desktop/main/window-titlebar.ts
index 1c499505..14ec9475 100644
--- a/apps/desktop/main/window-titlebar.ts
+++ b/apps/desktop/main/window-titlebar.ts
@@ -40,6 +40,10 @@ export function applyTitleBarOverlayColor(win: BrowserWindow | null | undefined,
   win?.setTitleBarOverlay(getTitleBarOverlayOptionsForColor(color))
 }
 
+export function resetCurrentTitleBarOverlayColor(): void {
+  currentTitleBarOverlayColor = null
+}
+
 function getReadableSymbolColor(hexColor: string): string {
   const match = /^#([0-9a-f]{6})$/i.exec(hexColor)
   if (!match) return '#52525b'