diff --git a/desktop/src/api/hahaOpenAIOAuth.ts b/desktop/src/api/hahaOpenAIOAuth.ts
new file mode 100644
index 00000000..2aefbea6
--- /dev/null
+++ b/desktop/src/api/hahaOpenAIOAuth.ts
@@ -0,0 +1,38 @@
+// desktop/src/api/hahaOpenAIOAuth.ts
+
+import { api, getBaseUrl } from './client'
+
+export type HahaOpenAIOAuthStatus =
+  | { loggedIn: false }
+  | {
+      loggedIn: true
+      expiresAt: number | null
+      email: string | null
+      accountId: string | null
+    }
+
+function currentServerPort(): number {
+  const port = new URL(getBaseUrl()).port
+  const parsed = Number.parseInt(port, 10)
+  if (!Number.isFinite(parsed) || parsed <= 0) {
+    throw new Error(`Cannot determine server port from baseUrl: ${getBaseUrl()}`)
+  }
+  return parsed
+}
+
+export const hahaOpenAIOAuthApi = {
+  start() {
+    return api.post<{ authorizeUrl: string; state: string }>(
+      '/api/haha-openai-oauth/start',
+      { serverPort: currentServerPort() },
+    )
+  },
+
+  status() {
+    return api.get<HahaOpenAIOAuthStatus>('/api/haha-openai-oauth')
+  },
+
+  logout() {
+    return api.delete<{ ok: true }>('/api/haha-openai-oauth')
+  },
+}
diff --git a/desktop/src/components/settings/ChatGPTOfficialLogin.tsx b/desktop/src/components/settings/ChatGPTOfficialLogin.tsx
new file mode 100644
index 00000000..4bbe0082
--- /dev/null
+++ b/desktop/src/components/settings/ChatGPTOfficialLogin.tsx
@@ -0,0 +1,104 @@
+// desktop/src/components/settings/ChatGPTOfficialLogin.tsx
+
+import { useEffect } from 'react'
+import { open as shellOpen } from '@tauri-apps/plugin-shell'
+import { LogIn, LogOut } from 'lucide-react'
+import { useHahaOpenAIOAuthStore } from '../../stores/hahaOpenAIOAuthStore'
+import { useTranslation } from '../../i18n'
+
+export function ChatGPTOfficialLogin() {
+  const t = useTranslation()
+  const {
+    status,
+    isLoading,
+    error,
+    fetchStatus,
+    login,
+    logout,
+    startPolling,
+    stopPolling,
+  } = useHahaOpenAIOAuthStore()
+
+  useEffect(() => {
+    void fetchStatus()
+    return () => stopPolling()
+  }, [fetchStatus, stopPolling])
+
+  const handleLogin = async () => {
+    try {
+      const { authorizeUrl } = await login()
+      try {
+        await shellOpen(authorizeUrl)
+        startPolling()
+      } catch (err) {
+        console.error('[ChatGPTOfficialLogin] shellOpen failed:', err)
+        useHahaOpenAIOAuthStore.setState({
+          error: t('settings.chatgptOfficialLogin.openBrowserFailed'),
+        })
+      }
+    } catch {
+      // store.login() errors are already captured into store.error
+    }
+  }
+
+  if (status === null) {
+    if (error) {
+      return (
+        <div data-testid="chatgpt-official-login" className="text-xs text-[var(--color-error)]">
+          {t('settings.chatgptOfficialLogin.errorPrefix')}{error}
+        </div>
+      )
+    }
+    return (
+      <div data-testid="chatgpt-official-login" className="text-xs text-[var(--color-text-tertiary)]">
+        {t('common.loading')}
+      </div>
+    )
+  }
+
+  if (status.loggedIn) {
+    const accountLabel = status.email || status.accountId || t('settings.chatgptOfficialLogin.accountUnknown')
+    return (
+      <div data-testid="chatgpt-official-login" className="flex items-center gap-3 text-sm">
+        <span className="text-[var(--color-success)]">
+          {t('settings.chatgptOfficialLogin.loggedInPrefix')} {accountLabel}
+        </span>
+        <button
+          type="button"
+          onClick={logout}
+          disabled={isLoading}
+          className="inline-flex items-center gap-1.5 rounded-md border border-[var(--color-border-separator)] bg-[var(--color-surface)] px-3 py-1 text-xs transition-colors hover:bg-[var(--color-surface-hover)] disabled:opacity-50"
+        >
+          <LogOut className="h-3.5 w-3.5" aria-hidden="true" />
+          {isLoading
+            ? t('settings.chatgptOfficialLogin.logoutProcessing')
+            : t('settings.chatgptOfficialLogin.logoutButton')}
+        </button>
+      </div>
+    )
+  }
+
+  return (
+    <div data-testid="chatgpt-official-login" className="flex flex-col gap-2">
+      <div className="text-sm text-[var(--color-text-secondary)]">
+        {t('settings.chatgptOfficialLogin.intro')}
+      </div>
+      <button
+        type="button"
+        onClick={handleLogin}
+        disabled={isLoading}
+        className="inline-flex items-center gap-2 self-start rounded-md bg-[image:var(--gradient-btn-primary)] px-4 py-2 text-sm text-[var(--color-btn-primary-fg)] shadow-[var(--shadow-button-primary)] transition-opacity hover:brightness-105 disabled:opacity-50"
+      >
+        <LogIn className="h-4 w-4" aria-hidden="true" />
+        {isLoading
+          ? t('settings.chatgptOfficialLogin.loginStarting')
+          : t('settings.chatgptOfficialLogin.loginButton')}
+      </button>
+      {error && (
+        <div className="text-xs text-[var(--color-error)]">
+          {t('settings.chatgptOfficialLogin.errorPrefix')}{error}
+        </div>
+      )}
+    </div>
+  )
+}
diff --git a/desktop/src/i18n/locales/en.ts b/desktop/src/i18n/locales/en.ts
index ad1f0d1f..0d57aa4a 100644
--- a/desktop/src/i18n/locales/en.ts
+++ b/desktop/src/i18n/locales/en.ts
@@ -271,6 +271,17 @@ export const en = {
   'settings.claudeOfficialLogin.errorPrefix': 'Error: ',
   'settings.claudeOfficialLogin.openBrowserFailed': 'Failed to open browser; please visit the authorization URL manually.',
 
+  // Settings > ChatGPT Official Login
+  'settings.chatgptOfficialLogin.intro': 'Sign in with ChatGPT to use GPT models from desktop sessions.',
+  'settings.chatgptOfficialLogin.loginButton': 'Sign in with ChatGPT',
+  'settings.chatgptOfficialLogin.loginStarting': 'Starting sign-in...',
+  'settings.chatgptOfficialLogin.logoutButton': 'Sign out',
+  'settings.chatgptOfficialLogin.logoutProcessing': 'Signing out...',
+  'settings.chatgptOfficialLogin.loggedInPrefix': 'Signed in as',
+  'settings.chatgptOfficialLogin.accountUnknown': 'ChatGPT account',
+  'settings.chatgptOfficialLogin.openBrowserFailed': 'Unable to open browser. Copy the authorization URL from server logs and open it manually.',
+  'settings.chatgptOfficialLogin.errorPrefix': 'ChatGPT OAuth error: ',
+
   // Settings > Providers
   'settings.providers.title': 'Providers',
   'settings.providers.description': 'Manage API providers for model access.',
diff --git a/desktop/src/i18n/locales/zh.ts b/desktop/src/i18n/locales/zh.ts
index 3bed1c29..392d090b 100644
--- a/desktop/src/i18n/locales/zh.ts
+++ b/desktop/src/i18n/locales/zh.ts
@@ -273,6 +273,17 @@ export const zh: Record<TranslationKey, string> = {
   'settings.claudeOfficialLogin.errorPrefix': '错误:',
   'settings.claudeOfficialLogin.openBrowserFailed': '无法打开浏览器,请手动访问授权链接。',
 
+  // Settings > ChatGPT Official Login
+  'settings.chatgptOfficialLogin.intro': '登录 ChatGPT 后,就可以在桌面端会话里使用 GPT 模型。',
+  'settings.chatgptOfficialLogin.loginButton': '登录 ChatGPT',
+  'settings.chatgptOfficialLogin.loginStarting': '正在启动登录...',
+  'settings.chatgptOfficialLogin.logoutButton': '退出登录',
+  'settings.chatgptOfficialLogin.logoutProcessing': '正在退出...',
+  'settings.chatgptOfficialLogin.loggedInPrefix': '已登录',
+  'settings.chatgptOfficialLogin.accountUnknown': 'ChatGPT 账号',
+  'settings.chatgptOfficialLogin.openBrowserFailed': '无法打开浏览器。请从服务端日志复制授权链接并手动打开。',
+  'settings.chatgptOfficialLogin.errorPrefix': 'ChatGPT OAuth 错误:',
+
   // Settings > Providers
   'settings.providers.title': '服务商',
   'settings.providers.description': '管理 API 服务商以访问模型。',
diff --git a/desktop/src/stores/hahaOpenAIOAuthStore.test.ts b/desktop/src/stores/hahaOpenAIOAuthStore.test.ts
new file mode 100644
index 00000000..5b6475dd
--- /dev/null
+++ b/desktop/src/stores/hahaOpenAIOAuthStore.test.ts
@@ -0,0 +1,97 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+
+const { startMock, statusMock, logoutMock } = vi.hoisted(() => ({
+  startMock: vi.fn(),
+  statusMock: vi.fn(),
+  logoutMock: vi.fn(),
+}))
+
+vi.mock('../api/hahaOpenAIOAuth', () => ({
+  hahaOpenAIOAuthApi: {
+    start: startMock,
+    status: statusMock,
+    logout: logoutMock,
+  },
+}))
+
+import { useHahaOpenAIOAuthStore } from './hahaOpenAIOAuthStore'
+
+const initialState = useHahaOpenAIOAuthStore.getState()
+
+describe('hahaOpenAIOAuthStore', () => {
+  beforeEach(() => {
+    vi.useFakeTimers()
+    startMock.mockReset()
+    statusMock.mockReset()
+    logoutMock.mockReset()
+    useHahaOpenAIOAuthStore.setState({
+      ...initialState,
+      status: null,
+      isPolling: false,
+      isLoading: false,
+      error: null,
+    })
+  })
+
+  afterEach(() => {
+    useHahaOpenAIOAuthStore.getState().stopPolling()
+    useHahaOpenAIOAuthStore.setState(initialState)
+    vi.useRealTimers()
+  })
+
+  it('login returns authorizeUrl without starting polling', async () => {
+    startMock.mockResolvedValue({
+      authorizeUrl: 'http://localhost:3456/callback/openai?state=openai-state',
+      state: 'openai-state',
+    })
+
+    const result = await useHahaOpenAIOAuthStore.getState().login()
+
+    expect(result.authorizeUrl).toContain('/callback/openai')
+    expect(useHahaOpenAIOAuthStore.getState().isPolling).toBe(false)
+  })
+
+  it('startPolling stops after OpenAI OAuth status becomes logged in', async () => {
+    statusMock
+      .mockResolvedValueOnce({ loggedIn: false })
+      .mockResolvedValueOnce({
+        loggedIn: true,
+        expiresAt: Date.now() + 60_000,
+        email: 'user@example.com',
+        accountId: 'acct_123',
+      })
+
+    useHahaOpenAIOAuthStore.getState().startPolling()
+    expect(useHahaOpenAIOAuthStore.getState().isPolling).toBe(true)
+
+    await vi.advanceTimersByTimeAsync(2_000)
+    expect(useHahaOpenAIOAuthStore.getState().isPolling).toBe(true)
+
+    await vi.advanceTimersByTimeAsync(2_000)
+    expect(useHahaOpenAIOAuthStore.getState().status).toMatchObject({
+      loggedIn: true,
+      email: 'user@example.com',
+      accountId: 'acct_123',
+    })
+    expect(useHahaOpenAIOAuthStore.getState().isPolling).toBe(false)
+  })
+
+  it('logout clears status and stops polling', async () => {
+    logoutMock.mockResolvedValue({ ok: true })
+    useHahaOpenAIOAuthStore.setState({
+      status: {
+        loggedIn: true,
+        expiresAt: Date.now() + 60_000,
+        email: 'user@example.com',
+        accountId: 'acct_123',
+      },
+    })
+    useHahaOpenAIOAuthStore.getState().startPolling()
+
+    await useHahaOpenAIOAuthStore.getState().logout()
+
+    expect(logoutMock).toHaveBeenCalledTimes(1)
+    expect(useHahaOpenAIOAuthStore.getState().status).toEqual({ loggedIn: false })
+    expect(useHahaOpenAIOAuthStore.getState().isPolling).toBe(false)
+  })
+})
diff --git a/desktop/src/stores/hahaOpenAIOAuthStore.ts b/desktop/src/stores/hahaOpenAIOAuthStore.ts
new file mode 100644
index 00000000..044ff33d
--- /dev/null
+++ b/desktop/src/stores/hahaOpenAIOAuthStore.ts
@@ -0,0 +1,101 @@
+// desktop/src/stores/hahaOpenAIOAuthStore.ts
+
+import { create } from 'zustand'
+import {
+  hahaOpenAIOAuthApi,
+  type HahaOpenAIOAuthStatus,
+} from '../api/hahaOpenAIOAuth'
+
+const POLL_INTERVAL_MS = 2_000
+
+type HahaOpenAIOAuthState = {
+  status: HahaOpenAIOAuthStatus | null
+  isPolling: boolean
+  isLoading: boolean
+  error: string | null
+
+  fetchStatus: () => Promise<void>
+  login: () => Promise<{ authorizeUrl: string }>
+  logout: () => Promise<void>
+  startPolling: () => void
+  stopPolling: () => void
+}
+
+export const useHahaOpenAIOAuthStore = create<HahaOpenAIOAuthState>((set, get) => {
+  let pollTimer: ReturnType<typeof setTimeout> | null = null
+
+  return {
+    status: null,
+    isPolling: false,
+    isLoading: false,
+    error: null,
+
+    fetchStatus: async () => {
+      try {
+        const status = await hahaOpenAIOAuthApi.status()
+        set({ status, error: null })
+      } catch (err) {
+        set({ error: err instanceof Error ? err.message : String(err) })
+      }
+    },
+
+    login: async () => {
+      set({ isLoading: true, error: null })
+      try {
+        const res = await hahaOpenAIOAuthApi.start()
+        set({ isLoading: false })
+        return { authorizeUrl: res.authorizeUrl }
+      } catch (err) {
+        set({
+          isLoading: false,
+          error: err instanceof Error ? err.message : String(err),
+        })
+        throw err
+      }
+    },
+
+    logout: async () => {
+      get().stopPolling()
+      set({ isLoading: true, error: null })
+      try {
+        await hahaOpenAIOAuthApi.logout()
+        set({ status: { loggedIn: false }, isLoading: false })
+      } catch (err) {
+        set({
+          isLoading: false,
+          error: err instanceof Error ? err.message : String(err),
+        })
+        throw err
+      }
+    },
+
+    startPolling: () => {
+      if (pollTimer) return
+      set({ isPolling: true })
+
+      const scheduleNext = () => {
+        pollTimer = setTimeout(async () => {
+          pollTimer = null
+          await get().fetchStatus()
+          const cur = get().status
+          if (cur && cur.loggedIn) {
+            get().stopPolling()
+            return
+          }
+          if (get().isPolling) {
+            scheduleNext()
+          }
+        }, POLL_INTERVAL_MS)
+      }
+      scheduleNext()
+    },
+
+    stopPolling: () => {
+      if (pollTimer) {
+        clearTimeout(pollTimer)
+        pollTimer = null
+      }
+      set({ isPolling: false })
+    },
+  }
+})