diff --git a/frontend/src/pages/orders/__tests__/index.spec.ts b/frontend/src/pages/orders/__tests__/index.spec.ts
index 81e8bf5..a82e0a4 100644
--- a/frontend/src/pages/orders/__tests__/index.spec.ts
+++ b/frontend/src/pages/orders/__tests__/index.spec.ts
@@ -19,6 +19,12 @@ Object.defineProperty(window, 'matchMedia', {
   }),
 })
 
+let mockRouteQuery: Record<string, string> = {}
+vi.mock('vue-router', () => ({
+  useRoute: () => ({ query: mockRouteQuery }),
+  useRouter: () => ({ push: vi.fn() }),
+}))
+
 vi.mock('@/utils/request', () => ({
   api: {
     get: vi.fn(),
@@ -313,6 +319,7 @@ describe('OrdersPage', () => {
     setActivePinia(createPinia())
     vi.restoreAllMocks()
     document.body.innerHTML = ''
+    mockRouteQuery = {}
   })
 
   afterEach(() => {
@@ -665,4 +672,37 @@ describe('OrdersPage', () => {
 
     expect(writeTextMock).toHaveBeenCalledWith('ORD-20260101-001')
   })
+
+  // ─── P18.2 URL 参数自动填充测试 ───────────────────────────
+
+  it('fills filter and fetches when auto_submit=1 with platform_order_id', async () => {
+    mockRouteQuery = { platform_order_id: 'ORD-FROM-URL', auto_submit: '1' }
+    const { api } = await mountPage()
+
+    const store = useOrderStore()
+    expect(store.filters.platform_order_id).toBe('ORD-FROM-URL')
+    expect(api.get).toHaveBeenCalledWith(
+      '/api/v1/orders',
+      expect.objectContaining({
+        platform_order_id: 'ORD-FROM-URL',
+        page: 1,
+      }),
+    )
+  })
+
+  it('does not fill filter when platform_order_id present but no auto_submit', async () => {
+    mockRouteQuery = { platform_order_id: 'ORD-FROM-URL' }
+    await mountPage()
+
+    const store = useOrderStore()
+    expect(store.filters.platform_order_id).toBe('')
+  })
+
+  it('does not fill filter when only auto_submit is present without platform_order_id', async () => {
+    mockRouteQuery = { auto_submit: '1' }
+    await mountPage()
+
+    const store = useOrderStore()
+    expect(store.filters.platform_order_id).toBe('')
+  })
 })
diff --git a/frontend/src/pages/orders/index.vue b/frontend/src/pages/orders/index.vue
index 5e95f1f..e4f6213 100644
--- a/frontend/src/pages/orders/index.vue
+++ b/frontend/src/pages/orders/index.vue
@@ -91,8 +91,21 @@ const paidDateRange = computed({
   },
 })
 
-onMounted(() => {
-  store.loadLookups()
+const route = useRoute()
+
+onMounted(async () => {
+  const hasAutoSubmit = route.query.auto_submit === '1'
+
+  if (hasAutoSubmit) {
+    await store.loadLookups()
+    if (route.query.platform_order_id) {
+      store.filters.platform_order_id = route.query.platform_order_id as string
+    }
+    store.pagination.page = 1
+  } else {
+    store.loadLookups()
+  }
+
   store.fetchOrders()
 })