diff --git a/web/app/components/datasets/metadata/metadata-document/__tests__/document-information.spec.tsx b/web/app/components/datasets/metadata/metadata-document/__tests__/document-information.spec.tsx
new file mode 100644
index 00000000000..4e0ce4e8e68
--- /dev/null
+++ b/web/app/components/datasets/metadata/metadata-document/__tests__/document-information.spec.tsx
@@ -0,0 +1,101 @@
+import { render, screen } from '@testing-library/react'
+import { describe, expect, it, vi } from 'vite-plus/test'
+import MetadataDocument from '../index'
+
+vi.mock('@/context/dataset-detail', () => ({
+  useDatasetDetailContext: () => ({ dataset: { embedding_available: true } }),
+}))
+
+vi.mock('@/service/knowledge/use-metadata', () => ({
+  useBatchUpdateDocMetadata: () => ({ mutateAsync: vi.fn() }),
+  useCreateMetaData: () => ({ mutateAsync: vi.fn() }),
+  useDocumentMetaData: () => ({ data: { doc_metadata: [] } }),
+  useDatasetMetaData: () => ({ data: { built_in_field_enabled: false } }),
+}))
+
+vi.mock('@/next/navigation', () => ({
+  useRouter: () => ({ push: vi.fn() }),
+}))
+
+vi.mock('@/hooks/use-timestamp', () => ({
+  default: () => ({
+    formatTime: (timestamp: number) => new Date(timestamp * 1000).toISOString(),
+  }),
+}))
+
+vi.mock('react-i18next', async () => {
+  const { createReactI18nextMock } = await import('@/test/i18n-mock')
+  return createReactI18nextMock({
+    'metadata.field.originInfo.originalFileSize': 'Original file size',
+    'metadata.field.originInfo.lastUpdateDate': 'Last update date',
+  })
+})
+
+type DocumentDetail = Parameters<typeof MetadataDocument>[0]['docDetail']
+
+const uploadFile = { name: 'handbook.txt', extension: 'txt', size: 497 }
+
+// The Console detail endpoint separates the upload reference from its details.
+const documentDetail: Partial<DocumentDetail> = {
+  id: 'document-1',
+  name: 'handbook.txt',
+  data_source_type: 'upload_file',
+  data_source_info: { upload_file_id: 'upload-1' },
+  data_source_detail_dict: {
+    upload_file: uploadFile,
+  },
+  created_at: Date.parse('2026-09-23T10:30:00Z') / 1000,
+  completed_at: Date.parse('2026-09-23T10:32:00Z') / 1000,
+  updated_at: Date.parse('2026-09-23T10:33:00Z') / 1000,
+}
+
+const renderDocument = (detail: Partial<DocumentDetail>) => (
+  <MetadataDocument
+    datasetId="dataset-1"
+    documentId="document-1"
+    docDetail={detail as DocumentDetail}
+  />
+)
+
+describe('Document information', () => {
+  it('shows the uploaded file size from the document detail response', () => {
+    render(renderDocument(documentDetail))
+
+    expect(screen.getByText('497.00 bytes')).toBeInTheDocument()
+  })
+
+  it('shows the last modification time and refreshes it when document details change', () => {
+    const { rerender } = render(renderDocument(documentDetail))
+
+    expect(screen.getByText('2026-09-23T10:33:00.000Z')).toBeInTheDocument()
+    expect(screen.queryByText('2026-09-23T10:32:00.000Z')).not.toBeInTheDocument()
+
+    rerender(
+      renderDocument({
+        ...documentDetail,
+        updated_at: Date.parse('2026-09-23T10:38:00Z') / 1000,
+      }),
+    )
+
+    expect(screen.getByText('2026-09-23T10:38:00.000Z')).toBeInTheDocument()
+    expect(screen.queryByText('2026-09-23T10:33:00.000Z')).not.toBeInTheDocument()
+  })
+
+  it.each(['notion_import', 'website_crawl'] as const)(
+    'keeps the missing-size placeholder for %s documents',
+    (dataSourceType) => {
+      render(
+        renderDocument({
+          ...documentDetail,
+          data_source_type: dataSourceType,
+          data_source_info: {},
+          data_source_detail_dict: {},
+        } as DocumentDetail),
+      )
+
+      expect(screen.getByText('Original file size').parentElement).toHaveTextContent(
+        'Original file size-',
+      )
+    },
+  )
+})
diff --git a/web/hooks/use-metadata.ts b/web/hooks/use-metadata.ts
index 6c01ba37e10..98c97aedfd1 100644
--- a/web/hooks/use-metadata.ts
+++ b/web/hooks/use-metadata.ts
@@ -344,7 +344,7 @@ export const useMetadataMap = (): MetadataMap => {
             ns: 'datasetDocuments',
           }),
         },
-        'data_source_info.upload_file.size': {
+        'data_source_detail_dict.upload_file.size': {
           label: t(($) => $[`${fieldPrefix}.originInfo.originalFileSize`], {
             ns: 'datasetDocuments',
           }),
@@ -358,7 +358,7 @@ export const useMetadataMap = (): MetadataMap => {
               t(($) => $['metadata.dateTimeFormat'], { ns: 'datasetDocuments' }) as string,
             ),
         },
-        completed_at: {
+        updated_at: {
           label: t(($) => $[`${fieldPrefix}.originInfo.lastUpdateDate`], {
             ns: 'datasetDocuments',
           }),