diff --git a/backend/app/document_service.py b/backend/app/document_service.py
index 959dd96..64bac50 100644
--- a/backend/app/document_service.py
+++ b/backend/app/document_service.py
@@ -1,11 +1,16 @@
 import base64
 import logging
+import re
 from datetime import datetime, timezone
 
 from app.text_extract import html_to_text, markdown_to_text
 
 logger = logging.getLogger(__name__)
 
+
+def _natural_sort_key(name: str) -> list:
+    return [int(part) if part.isdigit() else part for part in re.split(r"(\d+)", name)]
+
 ALLOWED_UPLOAD_EXTENSIONS = {".md", ".html", ".htm", ".png", ".jpg", ".jpeg", ".gif", ".webp"}
 MAX_UPLOAD_SIZE_BYTES = 10 * 1024 * 1024
 
@@ -76,6 +81,8 @@ class DocumentService:
                     "size": entry["size"],
                     "modifiedAt": entry["modifiedAt"],
                 })
+        folders.sort(key=_natural_sort_key)
+        files.sort(key=lambda f: _natural_sort_key(f["name"]))
         return {"folders": folders, "files": files}
 
     def get_document(self, key: str) -> dict:
@@ -135,3 +142,24 @@ class DocumentService:
         self.save_document(key, data, content_type)
         name = key.rsplit("/", 1)[-1]
         return {"key": key, "name": name, "size": len(data)}
+
+    def reindex_all(self) -> dict:
+        self._search_client.delete_all_documents()
+        keys = self._file_client.walk_files()
+        indexed = 0
+        failed = 0
+        for key in keys:
+            content_type = _guess_content_type(key)
+            if content_type == "application/octet-stream":
+                continue
+            try:
+                data = self._file_client.get_object(key)
+                text = self._extract_text(data, content_type)
+                title = key.rsplit("/", 1)[-1]
+                path = key.rsplit("/", 1)[0] if "/" in key else ""
+                self._search_client.index_document(key, path, title, text)
+                indexed += 1
+            except Exception:
+                logger.exception("Failed to reindex %s", key)
+                failed += 1
+        return {"indexed": indexed, "failed": failed, "total": len(keys)}
diff --git a/backend/app/local_file_client.py b/backend/app/local_file_client.py
index b0dd976..649e798 100644
--- a/backend/app/local_file_client.py
+++ b/backend/app/local_file_client.py
@@ -74,3 +74,13 @@ class LocalFileClient:
                 parent = parent.parent
             else:
                 break
+
+    def walk_files(self) -> list[str]:
+        """递归遍历所有文件，返回相对于 base_dir 的 key 列表（不含目录）"""
+        result = []
+        for root, _dirs, filenames in os.walk(self._base_dir):
+            for filename in filenames:
+                full_path = Path(root) / filename
+                rel_path = full_path.relative_to(self._base_dir)
+                result.append(str(rel_path).replace(os.sep, "/"))
+        return result
diff --git a/backend/app/routers/search.py b/backend/app/routers/search.py
index a2d3d2b..2c5d0ac 100644
--- a/backend/app/routers/search.py
+++ b/backend/app/routers/search.py
@@ -1,6 +1,7 @@
 from fastapi import APIRouter, Depends
 
-from app.dependencies import get_search_client
+from app.dependencies import get_document_service, get_search_client
+from app.document_service import DocumentService
 from app.search_client import SearchClient
 
 router = APIRouter()
@@ -9,3 +10,8 @@ router = APIRouter()
 @router.get("/api/search")
 def search(q: str = "", client: SearchClient = Depends(get_search_client)):
     return {"results": client.search(q)}
+
+
+@router.post("/api/search/reindex")
+def reindex(service: DocumentService = Depends(get_document_service)):
+    return service.reindex_all()
diff --git a/backend/app/search_client.py b/backend/app/search_client.py
index bfa9650..5d561c2 100644
--- a/backend/app/search_client.py
+++ b/backend/app/search_client.py
@@ -24,6 +24,10 @@ class SearchClient:
         index = self._client.index(self._index_name)
         index.delete_document(_encode_key(key))
 
+    def delete_all_documents(self) -> None:
+        index = self._client.index(self._index_name)
+        index.delete_all_documents()
+
     def search(self, query: str) -> list[dict]:
         index = self._client.index(self._index_name)
         response = index.search(query, {
diff --git a/backend/tests/test_document_service.py b/backend/tests/test_document_service.py
index 2d25338..4ad383e 100644
--- a/backend/tests/test_document_service.py
+++ b/backend/tests/test_document_service.py
@@ -35,6 +35,9 @@ class FakeFileClient:
         del self.stored[key]
         self.deleted_keys.append(key)
 
+    def walk_files(self):
+        return list(self.stored.keys())
+
 
 class FakeSearchClient:
     def __init__(self, fail_on_index=False, fail_on_delete=False):
@@ -42,6 +45,7 @@ class FakeSearchClient:
         self.deleted = []
         self.fail_on_index = fail_on_index
         self.fail_on_delete = fail_on_delete
+        self.cleared = False
 
     def index_document(self, key, path, title, content):
         if self.fail_on_index:
@@ -53,6 +57,27 @@ class FakeSearchClient:
             raise RuntimeError("meilisearch unavailable")
         self.deleted.append(key)
 
+    def delete_all_documents(self):
+        self.cleared = True
+
+
+def test_list_documents_sorts_files_naturally_by_numeric_prefix():
+    file_client = FakeFileClient()
+    file_client.entries = [
+        {"key": "8.10 系统设计.md", "is_dir": False, "size": 1, "modifiedAt": None},
+        {"key": "8.1 GMP调度.md", "is_dir": False, "size": 1, "modifiedAt": None},
+        {"key": "8.2 Channel.md", "is_dir": False, "size": 1, "modifiedAt": None},
+    ]
+    service = DocumentService(file_client, FakeSearchClient())
+
+    result = service.list_documents("")
+
+    assert [f["name"] for f in result["files"]] == [
+        "8.1 GMP调度.md",
+        "8.2 Channel.md",
+        "8.10 系统设计.md",
+    ]
+
 
 def test_list_documents_at_root_returns_folders_and_files():
     file_client = FakeFileClient()
@@ -240,3 +265,28 @@ def test_upload_document_accepts_allowed_image_extension():
 
     assert result == {"key": "产品文档/图片.png", "name": "图片.png", "size": len(data)}
     assert file_client.stored["产品文档/图片.png"] == data
+
+
+def test_reindex_all_clears_index_then_reindexes_every_supported_file():
+    file_client = FakeFileClient()
+    file_client.stored["产品文档/架构设计.md"] = "# 架构设计".encode("utf-8")
+    file_client.stored["产品文档/图片.png"] = b"\x89PNG\r\n\x1a\n"
+    search_client = FakeSearchClient()
+    service = DocumentService(file_client, search_client)
+
+    result = service.reindex_all()
+
+    assert search_client.cleared
+    assert result == {"indexed": 1, "failed": 0, "total": 2}
+    assert search_client.indexed[0]["key"] == "产品文档/架构设计.md"
+
+
+def test_reindex_all_counts_failures_without_raising():
+    file_client = FakeFileClient()
+    file_client.stored["产品文档/架构设计.md"] = "# 架构设计".encode("utf-8")
+    search_client = FakeSearchClient(fail_on_index=True)
+    service = DocumentService(file_client, search_client)
+
+    result = service.reindex_all()
+
+    assert result == {"indexed": 0, "failed": 1, "total": 1}
diff --git a/backend/tests/test_local_file_client.py b/backend/tests/test_local_file_client.py
index aa1a59e..1204da5 100644
--- a/backend/tests/test_local_file_client.py
+++ b/backend/tests/test_local_file_client.py
@@ -52,3 +52,21 @@ def test_list_objects_returns_empty_list_for_missing_prefix(client):
 def test_resolve_path_rejects_path_traversal(client):
     with pytest.raises(ValueError):
         client.get_object("../../etc/passwd")
+
+
+def test_walk_files_returns_all_nested_file_keys(client):
+    client.put_object("产品文档/架构设计.md", b"# hi", "text/markdown")
+    client.put_object("产品文档/子目录/详情.md", "# 详情".encode("utf-8"), "text/markdown")
+    client.put_object("团队规范/编码规范.md", b"# rules", "text/markdown")
+
+    result = client.walk_files()
+
+    assert sorted(result) == sorted([
+        "产品文档/架构设计.md",
+        "产品文档/子目录/详情.md",
+        "团队规范/编码规范.md",
+    ])
+
+
+def test_walk_files_returns_empty_list_when_no_files(client):
+    assert client.walk_files() == []
diff --git a/backend/tests/test_routers_search.py b/backend/tests/test_routers_search.py
index 818f9ff..98618b6 100644
--- a/backend/tests/test_routers_search.py
+++ b/backend/tests/test_routers_search.py
@@ -2,7 +2,7 @@ import pytest
 from fastapi.testclient import TestClient
 
 from app.main import app
-from app.dependencies import get_search_client
+from app.dependencies import get_document_service, get_search_client
 
 
 class FakeSearchClient:
@@ -50,3 +50,29 @@ def test_search_returns_empty_results_for_no_match(client):
 def test_search_passes_query_string_to_search_client(client):
     client.get("/api/search", params={"q": "Garage"})
     assert client.fake_client.queries == ["Garage"]
+
+
+class FakeDocumentService:
+    def __init__(self):
+        self.reindex_called = False
+
+    def reindex_all(self):
+        self.reindex_called = True
+        return {"indexed": 3, "failed": 0, "total": 3}
+
+
+@pytest.fixture
+def reindex_client():
+    fake_service = FakeDocumentService()
+    app.dependency_overrides[get_document_service] = lambda: fake_service
+    with TestClient(app) as test_client:
+        test_client.fake_service = fake_service
+        yield test_client
+    app.dependency_overrides.clear()
+
+
+def test_reindex_triggers_full_reindex_and_returns_summary(reindex_client):
+    response = reindex_client.post("/api/search/reindex")
+    assert response.status_code == 200
+    assert response.json() == {"indexed": 3, "failed": 0, "total": 3}
+    assert reindex_client.fake_service.reindex_called
diff --git a/frontend/src/App.tsx b/frontend/src/App.tsx
index 08ab843..b1de9ce 100644
--- a/frontend/src/App.tsx
+++ b/frontend/src/App.tsx
@@ -4,6 +4,7 @@ import DocumentEditor from './components/DocumentEditor';
 import SearchBar from './components/SearchBar';
 import SearchResults from './components/SearchResults';
 import UploadButton from './components/UploadButton';
+import ReindexButton from './components/ReindexButton';
 import type { SearchResult, UploadDocumentResponse } from './api/client';
 
 export default function App() {
@@ -66,6 +67,7 @@ export default function App() {
           DocHub <span className="subtitle">档案 · 检索</span>
         </h1>
         <SearchBar value={searchQuery} onQueryChange={handleQueryChange} onResults={handleResults} />
+        <ReindexButton />
         <UploadButton path={uploadPath} onUploaded={handleUploaded} />
       </div>
       <div className="body">
diff --git a/frontend/src/api/client.ts b/frontend/src/api/client.ts
index 6f1e9a9..cc8e7c3 100644
--- a/frontend/src/api/client.ts
+++ b/frontend/src/api/client.ts
@@ -116,3 +116,17 @@ export async function search(query: string): Promise<SearchResponse> {
   }
   return response.json();
 }
+
+export interface ReindexResponse {
+  indexed: number;
+  failed: number;
+  total: number;
+}
+
+export async function reindexAll(): Promise<ReindexResponse> {
+  const response = await fetch(`${API_BASE_URL}/api/search/reindex`, { method: 'POST' });
+  if (!response.ok) {
+    throw new Error(`Failed to reindex: ${response.status}`);
+  }
+  return response.json();
+}
diff --git a/frontend/src/components/DocumentEditor.tsx b/frontend/src/components/DocumentEditor.tsx
index b6d20c8..7b47c3a 100644
--- a/frontend/src/components/DocumentEditor.tsx
+++ b/frontend/src/components/DocumentEditor.tsx
@@ -121,7 +121,12 @@ export default function DocumentEditor({ documentKey, onDirtyChange, onDeleted }
         </div>
       </div>
       <div className="editor-area">
-        <Editor value={content} onChange={handleChange} language={contentType === 'text/markdown' ? 'markdown' : 'html'} />
+        <Editor
+          value={content}
+          onChange={handleChange}
+          language={contentType === 'text/markdown' ? 'markdown' : 'html'}
+          options={{ automaticLayout: true }}
+        />
       </div>
     </div>
   );
diff --git a/frontend/src/components/ReindexButton.tsx b/frontend/src/components/ReindexButton.tsx
new file mode 100644
index 0000000..c76b871
--- /dev/null
+++ b/frontend/src/components/ReindexButton.tsx
@@ -0,0 +1,41 @@
+import { useState } from 'react';
+import { reindexAll } from '../api/client';
+
+export default function ReindexButton() {
+  const [isRunning, setIsRunning] = useState(false);
+  const [message, setMessage] = useState<string | null>(null);
+  const [isError, setIsError] = useState(false);
+
+  function handleClick() {
+    setIsRunning(true);
+    setMessage(null);
+    setIsError(false);
+    reindexAll()
+      .then((result) => {
+        setMessage(`已重建索引 ${result.indexed}/${result.total}`);
+        setIsError(result.failed > 0);
+        setIsRunning(false);
+      })
+      .catch((err) => {
+        setMessage(err instanceof Error ? err.message : '重建索引失败');
+        setIsError(true);
+        setIsRunning(false);
+      });
+  }
+
+  return (
+    <div className="reindex-control">
+      <button className="btn-secondary" onClick={handleClick} disabled={isRunning}>
+        {isRunning ? '重建中…' : '重建索引'}
+      </button>
+      {message && (
+        <span
+          className={isError ? 'reindex-message error' : 'reindex-message'}
+          data-testid="reindex-message"
+        >
+          {message}
+        </span>
+      )}
+    </div>
+  );
+}
diff --git a/frontend/src/styles.css b/frontend/src/styles.css
index 7973700..0aff619 100644
--- a/frontend/src/styles.css
+++ b/frontend/src/styles.css
@@ -164,6 +164,23 @@ body {
   background: var(--pine-deep);
 }
 
+.reindex-control {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.reindex-message {
+  font-family: 'IBM Plex Mono', monospace;
+  font-size: 11px;
+  color: var(--ash);
+  white-space: nowrap;
+}
+
+.reindex-message.error {
+  color: #b3432f;
+}
+
 /* ---------- Body layout ---------- */
 .body {
   flex: 1;
@@ -233,6 +250,7 @@ body {
 
 .tree-children {
   overflow: hidden;
+  padding-left: 14px;
 }
 
 .chevron {
diff --git a/frontend/tests/api/client.test.ts b/frontend/tests/api/client.test.ts
index e5dce8d..fdc76e9 100644
--- a/frontend/tests/api/client.test.ts
+++ b/frontend/tests/api/client.test.ts
@@ -1,5 +1,5 @@
 import { test, expect, vi, beforeEach } from 'vitest';
-import { listDocuments, getDocument, saveDocument, deleteDocument, uploadDocument, search } from '../../src/api/client';
+import { listDocuments, getDocument, saveDocument, deleteDocument, uploadDocument, search, reindexAll } from '../../src/api/client';
 
 beforeEach(() => {
   vi.restoreAllMocks();
@@ -125,3 +125,22 @@ test('search calls GET /api/search with the q query param and returns parsed JSO
   expect(globalThis.fetch).toHaveBeenCalledWith(`/api/search?q=${encodeURIComponent('检索')}`);
   expect(result).toEqual(mockResponse);
 });
+
+test('reindexAll posts to /api/search/reindex and returns parsed JSON', async () => {
+  const mockResponse = { indexed: 5, failed: 0, total: 5 };
+  globalThis.fetch = vi.fn().mockResolvedValue({
+    ok: true,
+    json: () => Promise.resolve(mockResponse),
+  }) as unknown as typeof fetch;
+
+  const result = await reindexAll();
+
+  expect(globalThis.fetch).toHaveBeenCalledWith('/api/search/reindex', { method: 'POST' });
+  expect(result).toEqual(mockResponse);
+});
+
+test('reindexAll throws when the response is not ok', async () => {
+  globalThis.fetch = vi.fn().mockResolvedValue({ ok: false, status: 500 }) as unknown as typeof fetch;
+
+  await expect(reindexAll()).rejects.toThrow('Failed to reindex: 500');
+});
diff --git a/frontend/tests/components/ReindexButton.test.tsx b/frontend/tests/components/ReindexButton.test.tsx
new file mode 100644
index 0000000..803f1fd
--- /dev/null
+++ b/frontend/tests/components/ReindexButton.test.tsx
@@ -0,0 +1,71 @@
+import { render, screen, waitFor } from '@testing-library/react';
+import userEvent from '@testing-library/user-event';
+import { vi, test, expect, beforeEach } from 'vitest';
+import ReindexButton from '../../src/components/ReindexButton';
+import { reindexAll } from '../../src/api/client';
+
+vi.mock('../../src/api/client');
+
+beforeEach(() => {
+  vi.mocked(reindexAll).mockReset();
+});
+
+test('clicking the button triggers reindexAll and shows the result summary', async () => {
+  vi.mocked(reindexAll).mockResolvedValue({ indexed: 5, failed: 0, total: 5 });
+  const user = userEvent.setup();
+
+  render(<ReindexButton />);
+  await user.click(screen.getByRole('button', { name: '重建索引' }));
+
+  expect(reindexAll).toHaveBeenCalledTimes(1);
+  await waitFor(() => {
+    expect(screen.getByTestId('reindex-message')).toHaveTextContent('已重建索引 5/5');
+  });
+});
+
+test('shows an error style message when some documents fail to index', async () => {
+  vi.mocked(reindexAll).mockResolvedValue({ indexed: 3, failed: 2, total: 5 });
+  const user = userEvent.setup();
+
+  render(<ReindexButton />);
+  await user.click(screen.getByRole('button', { name: '重建索引' }));
+
+  await waitFor(() => {
+    const message = screen.getByTestId('reindex-message');
+    expect(message).toHaveTextContent('已重建索引 3/5');
+    expect(message).toHaveClass('error');
+  });
+});
+
+test('shows an error message when the request fails', async () => {
+  vi.mocked(reindexAll).mockRejectedValue(new Error('Failed to reindex: 500'));
+  const user = userEvent.setup();
+
+  render(<ReindexButton />);
+  await user.click(screen.getByRole('button', { name: '重建索引' }));
+
+  await waitFor(() => {
+    expect(screen.getByTestId('reindex-message')).toHaveTextContent('Failed to reindex: 500');
+  });
+});
+
+test('disables the button while the request is in flight', async () => {
+  let resolveFn: (value: { indexed: number; failed: number; total: number }) => void = () => {};
+  vi.mocked(reindexAll).mockReturnValue(
+    new Promise((resolve) => {
+      resolveFn = resolve;
+    }),
+  );
+  const user = userEvent.setup();
+
+  render(<ReindexButton />);
+  const button = screen.getByRole('button', { name: '重建索引' });
+  await user.click(button);
+
+  expect(screen.getByRole('button', { name: '重建中…' })).toBeDisabled();
+
+  resolveFn({ indexed: 1, failed: 0, total: 1 });
+  await waitFor(() => {
+    expect(screen.getByRole('button', { name: '重建索引' })).not.toBeDisabled();
+  });
+});