diff --git a/apps/desktop/src/renderer/features/editor/CodeBlockView.tsx b/apps/desktop/src/renderer/features/editor/CodeBlockView.tsx
new file mode 100644
index 0000000..08e65f5
--- /dev/null
+++ b/apps/desktop/src/renderer/features/editor/CodeBlockView.tsx
@@ -0,0 +1,47 @@
+import { NodeViewWrapper, NodeViewContent, type NodeViewProps } from '@tiptap/react';
+
+// FR-E5 代码块语言切换：代码块顶部语言下拉（Shell/YAML/JSON/JS/TS/Python 等）
+const LANGS: { label: string; value: string }[] = [
+  { label: '纯文本', value: 'plaintext' },
+  { label: 'Shell', value: 'shell' },
+  { label: 'Bash', value: 'bash' },
+  { label: 'YAML', value: 'yaml' },
+  { label: 'JSON', value: 'json' },
+  { label: 'JavaScript', value: 'javascript' },
+  { label: 'TypeScript', value: 'typescript' },
+  { label: 'Python', value: 'python' },
+  { label: 'SQL', value: 'sql' },
+  { label: 'CSS', value: 'css' },
+  { label: 'SCSS', value: 'scss' },
+  { label: 'HTML/XML', value: 'xml' },
+  { label: 'Markdown', value: 'markdown' },
+  { label: 'C', value: 'c' },
+  { label: 'C++', value: 'cpp' },
+  { label: 'C#', value: 'csharp' },
+  { label: 'Go', value: 'go' },
+  { label: 'Rust', value: 'rust' },
+  { label: 'Java', value: 'java' },
+  { label: 'INI', value: 'ini' },
+  { label: 'Diff', value: 'diff' },
+];
+
+export function CodeBlockView({ node, updateAttributes, selected }: NodeViewProps) {
+  const language = (node.attrs.language as string) || '';
+  const codeClass = language ? `language-${language} hljs` : 'hljs';
+  return (
+    <NodeViewWrapper as="div" style={{ background: '#161616', borderRadius: 6, margin: '0.6em 0', overflow: 'hidden', outline: selected ? '1px solid #4a6a8a' : 'none' }}>
+      <div contentEditable={false} style={{ display: 'flex', justifyContent: 'flex-end', padding: '4px 8px', borderBottom: '1px solid #2a2a2a' }}>
+        <select
+          value={language || 'plaintext'}
+          onChange={e => updateAttributes({ language: e.target.value })}
+          style={{ background: '#222', color: '#ccc', border: '1px solid #444', borderRadius: 4, fontSize: 12, padding: '1px 4px', cursor: 'pointer' }}
+        >
+          {LANGS.map(l => <option key={l.value} value={l.value}>{l.label}</option>)}
+        </select>
+      </div>
+      <pre style={{ margin: 0, padding: '12px 16px', overflow: 'auto', background: 'transparent', borderRadius: 0 }}>
+        <NodeViewContent as={"code" as any} className={codeClass} />
+      </pre>
+    </NodeViewWrapper>
+  );
+}
diff --git a/apps/desktop/src/renderer/features/editor/TiptapEditor.tsx b/apps/desktop/src/renderer/features/editor/TiptapEditor.tsx
index d7af543..fde0886 100644
--- a/apps/desktop/src/renderer/features/editor/TiptapEditor.tsx
+++ b/apps/desktop/src/renderer/features/editor/TiptapEditor.tsx
@@ -1,5 +1,5 @@
 import { useEffect, useRef } from 'react';
-import { useEditor, EditorContent } from '@tiptap/react';
+import { useEditor, EditorContent, ReactNodeViewRenderer } from '@tiptap/react';
 import StarterKit from '@tiptap/starter-kit';
 import TaskList from '@tiptap/extension-task-list';
 import TaskItem from '@tiptap/extension-task-item';
@@ -19,9 +19,15 @@ import { EditorToolbar } from './EditorToolbar';
 import { FindReplace } from './FindReplace';
 import { SlashMenu } from './SlashMenu';
 import { BlockOps } from './BlockOps';
+import { CodeBlockView } from './CodeBlockView';
 
 const lowlight = createLowlight(common);
 
+// FR-E5：代码块自定义节点视图——顶部语言下拉 + 保留 lowlight 装饰高亮
+const CodeBlock = CodeBlockLowlight.extend({
+  addNodeView() { return ReactNodeViewRenderer(CodeBlockView); },
+});
+
 export function TiptapEditor() {
   const { currentPath, body, setBody } = useStore();
   const skipUpdate = useRef(false);
@@ -30,7 +36,7 @@ export function TiptapEditor() {
   const editor = useEditor({
     extensions: [
       StarterKit.configure({ codeBlock: false }),
-      CodeBlockLowlight.configure({ lowlight }),
+      CodeBlock.configure({ lowlight }),
       TaskList,
       TaskItem.configure({ nested: true }),
       Table.configure({ resizable: true }), TableRow, TableCell, TableHeader,
diff --git a/apps/desktop/src/renderer/styles.css b/apps/desktop/src/renderer/styles.css
index 66ec921..9627e40 100644
--- a/apps/desktop/src/renderer/styles.css
+++ b/apps/desktop/src/renderer/styles.css
@@ -26,6 +26,18 @@ html, body, #root { margin: 0; height: 100%; }
   background: #161616; padding: 12px 16px; border-radius: 6px; overflow: auto;
 }
 .tiptap-wrap .ProseMirror pre code { background: none; padding: 0; }
+/* highlight.js 暗色主题（CodeBlockLowlight 装饰 span，FR-E5） */
+.tiptap-wrap .ProseMirror .hljs { color: #abb2bf; }
+.tiptap-wrap .ProseMirror .hljs-comment, .tiptap-wrap .ProseMirror .hljs-quote { color: #5c6370; font-style: italic; }
+.tiptap-wrap .ProseMirror .hljs-doctag, .tiptap-wrap .ProseMirror .hljs-keyword, .tiptap-wrap .ProseMirror .hljs-formula, .tiptap-wrap .ProseMirror .hljs-name, .tiptap-wrap .ProseMirror .hljs-section, .tiptap-wrap .ProseMirror .hljs-selector-tag, .tiptap-wrap .ProseMirror .hljs-tag { color: #e06c75; }
+.tiptap-wrap .ProseMirror .hljs-addition, .tiptap-wrap .ProseMirror .hljs-attribute, .tiptap-wrap .ProseMirror .hljs-attr, .tiptap-wrap .ProseMirror .hljs-string, .tiptap-wrap .ProseMirror .hljs-template-tag, .tiptap-wrap .ProseMirror .hljs-template-variable, .tiptap-wrap .ProseMirror .hljs-value { color: #98c379; }
+.tiptap-wrap .ProseMirror .hljs-built_in, .tiptap-wrap .ProseMirror .hljs-class .hljs-title, .tiptap-wrap .ProseMirror .hljs-title, .tiptap-wrap .ProseMirror .hljs-title.class_, .tiptap-wrap .ProseMirror .hljs-type { color: #e6c07b; }
+.tiptap-wrap .ProseMirror .hljs-function .hljs-title, .tiptap-wrap .ProseMirror .hljs-title.function_ { color: #61afef; }
+.tiptap-wrap .ProseMirror .hljs-literal, .tiptap-wrap .ProseMirror .hljs-number, .tiptap-wrap .ProseMirror .hljs-operator, .tiptap-wrap .ProseMirror .hljs-variable, .tiptap-wrap .ProseMirror .hljs-params { color: #d19a66; }
+.tiptap-wrap .ProseMirror .hljs-bullet, .tiptap-wrap .ProseMirror .hljs-link, .tiptap-wrap .ProseMirror .hljs-meta, .tiptap-wrap .ProseMirror .hljs-regexp, .tiptap-wrap .ProseMirror .hljs-selector-attr, .tiptap-wrap .ProseMirror .hljs-selector-class, .tiptap-wrap .ProseMirror .hljs-selector-id, .tiptap-wrap .ProseMirror .hljs-symbol, .tiptap-wrap .ProseMirror .hljs-variable.constant_ { color: #56b6c2; }
+.tiptap-wrap .ProseMirror .hljs-deletion { color: #e06c75; }
+.tiptap-wrap .ProseMirror .hljs-emphasis { font-style: italic; }
+.tiptap-wrap .ProseMirror .hljs-strong { font-weight: 700; }
 .tiptap-wrap .ProseMirror blockquote {
   border-left: 3px solid #444; padding-left: 12px; color: #aaa; margin: 0.6em 0;
 }
diff --git a/apps/desktop/tests/e2e/editor-codeblock.spec.ts b/apps/desktop/tests/e2e/editor-codeblock.spec.ts
new file mode 100644
index 0000000..e5368a1
--- /dev/null
+++ b/apps/desktop/tests/e2e/editor-codeblock.spec.ts
@@ -0,0 +1,59 @@
+import { test, expect } from '@playwright/test';
+import { _electron as electron } from 'playwright';
+import { promises as fs } from 'node:fs';
+import nodePath from 'node:path';
+import os from 'node:os';
+
+const MAIN_JS = nodePath.join(process.cwd(), 'dist-electron/main/index.js');
+
+async function launch(userData: string) {
+  const app = await electron.launch({ args: ['--user-data-dir=' + userData, MAIN_JS] });
+  const page = await app.firstWindow();
+  await page.waitForLoadState('domcontentloaded');
+  const invoke = (ch: string, args: any) => page.evaluate(({ ch, args }) => (globalThis as any).dsh.invoke(ch, args), { ch, args });
+  return { app, page, invoke };
+}
+
+// FR-E5 代码块语言切换：每个代码块顶部语言下拉 -> 切换 language 属性
+test('FR-E5：代码块语言下拉切换生效', async () => {
+  const tmp = await fs.mkdtemp(nodePath.join(os.tmpdir(), 'hn-e5-'));
+  const userData = nodePath.join(tmp, 'userdata');
+  const vault = nodePath.join(tmp, 'vault');
+  await fs.mkdir(userData, { recursive: true });
+  await fs.mkdir(vault, { recursive: true });
+
+  const a = await launch(userData);
+  await a.invoke('vault:switch', { root: vault });
+
+  await a.page.getByRole('button', { name: /新建文档/ }).click();
+  await a.page.getByPlaceholder(/输入文档标题/).fill('代码块');
+  await a.page.getByPlaceholder(/输入文档标题/).press('Enter');
+  await expect(a.page.getByTestId('tabbar').getByText('代码块', { exact: true })).toBeVisible({ timeout: 10000 });
+
+  const editor = a.page.locator('.ProseMirror');
+  await editor.click();
+  // 插入代码块并输入内容
+  await a.page.locator('button[title="代码块 Ctrl+Shift+M"]').click();
+  await a.page.keyboard.type('key: value');
+
+  // 代码块顶部应渲染语言下拉
+  const select = a.page.locator('.ProseMirror select');
+  await expect(select).toBeVisible({ timeout: 10000 });
+
+  // 切换到 YAML -> code 元素带 language-yaml
+  await select.selectOption('yaml');
+  let cls: string = await a.page.locator('.ProseMirror pre code').evaluate(el => (el as HTMLElement).className);
+  expect(cls).toContain('language-yaml');
+
+  // 切换到 JSON -> language-json
+  await select.selectOption('json');
+  cls = await a.page.locator('.ProseMirror pre code').evaluate(el => (el as HTMLElement).className);
+  expect(cls).toContain('language-json');
+
+  // 切换到 TypeScript -> language-typescript
+  await select.selectOption('typescript');
+  cls = await a.page.locator('.ProseMirror pre code').evaluate(el => (el as HTMLElement).className);
+  expect(cls).toContain('language-typescript');
+
+  await a.app.close();
+});