diff --git a/backend/app/api/v1/files.py b/backend/app/api/v1/files.py
index 8c826ef..0dc4f41 100644
--- a/backend/app/api/v1/files.py
+++ b/backend/app/api/v1/files.py
@@ -683,4 +683,43 @@ async def export_directory(
         headers={
             "Content-Disposition": f"attachment; filename={zip_filename}"
         }
+    )
+
+
+@router.get("/{project_id}/export-pdf")
+async def export_pdf(
+    project_id: int,
+    path: str,
+    request: Request,
+    current_user: User = Depends(get_user_from_token_or_query),
+    db: AsyncSession = Depends(get_db)
+):
+    """已登录用户导出 Markdown 为 PDF"""
+    import re
+    from urllib.parse import quote
+    from app.services.pdf_service import pdf_service
+
+    project = await check_project_access(project_id, current_user, db)
+
+    file_path = storage_service.get_secure_path(project.storage_key, path)
+    if not file_path.exists() or not file_path.is_file():
+        raise HTTPException(status_code=404, detail="文件不存在")
+
+    content = await storage_service.read_file(file_path)
+    filename = Path(path).stem + ".pdf"
+
+    # 将 API 图片 URL 转为文件系统相对路径
+    content = re.sub(r'/api/v1/files/\d+/assets/', '_assets/', content)
+
+    project_root = storage_service.get_secure_path(project.storage_key)
+    pdf_buffer = await pdf_service.md_to_pdf(content, title=filename, base_url=str(project_root))
+
+    encoded_filename = quote(filename)
+    return StreamingResponse(
+        pdf_buffer,
+        media_type="application/pdf",
+        headers={
+            "Content-Disposition": f"attachment; filename*=UTF-8''{encoded_filename}",
+            "Content-Type": "application/pdf"
+        }
     )
\ No newline at end of file
diff --git a/backend/requirements.txt b/backend/requirements.txt
index d7d6095..4d00991 100644
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -47,3 +47,4 @@ websockets==15.0.1
 Whoosh==2.7.4
 markdown==3.5.2
 weasyprint==61.2
+pydyf<0.11.0
diff --git a/frontend/src/api/file.js b/frontend/src/api/file.js
index 86b742d..26f0064 100644
--- a/frontend/src/api/file.js
+++ b/frontend/src/api/file.js
@@ -129,3 +129,11 @@ export function getDocumentUrl(projectId, path) {
   const encodedPath = path.split('/').map(part => encodeURIComponent(part)).join('/')
   return `/api/v1/files/${projectId}/document/${encodedPath}`
 }
+
+/**
+ * 导出 Markdown 为 PDF（已登录用户）
+ */
+export function getExportPdfUrl(projectId, path) {
+  const encodedPath = encodeURIComponent(path)
+  return `/api/v1/files/${projectId}/export-pdf?path=${encodedPath}`
+}
diff --git a/frontend/src/components/DocFloatActions/DocFloatActions.jsx b/frontend/src/components/DocFloatActions/DocFloatActions.jsx
new file mode 100644
index 0000000..9a85079
--- /dev/null
+++ b/frontend/src/components/DocFloatActions/DocFloatActions.jsx
@@ -0,0 +1,37 @@
+import { FloatButton, Tooltip } from 'antd'
+import { MenuOutlined, FilePdfOutlined, VerticalAlignTopOutlined } from '@ant-design/icons'
+
+/**
+ * 文档浮动操作按钮组（导出 PDF + 回到顶部）
+ * @param {object}   props
+ * @param {function} props.onExportPDF  - 导出 PDF 回调
+ * @param {React.RefObject} props.scrollRef - 滚动容器 ref
+ * @param {number}   [props.right=24]   - 距右侧距离
+ */
+export default function DocFloatActions({ onExportPDF, scrollRef, right = 24 }) {
+  return (
+    <FloatButton.Group
+      trigger="hover"
+      type="primary"
+      icon={<MenuOutlined />}
+      style={{ right }}
+    >
+      <Tooltip title="导出 PDF" placement="left">
+        <FloatButton
+          icon={<FilePdfOutlined />}
+          onClick={onExportPDF}
+        />
+      </Tooltip>
+      <Tooltip title="回到顶部" placement="left">
+        <FloatButton
+          icon={<VerticalAlignTopOutlined />}
+          onClick={() => {
+            if (scrollRef?.current) {
+              scrollRef.current.scrollTo({ top: 0, behavior: 'smooth' })
+            }
+          }}
+        />
+      </Tooltip>
+    </FloatButton.Group>
+  )
+}
diff --git a/frontend/src/pages/Document/DocumentPage.jsx b/frontend/src/pages/Document/DocumentPage.jsx
index 64f6675..1f5a6e7 100644
--- a/frontend/src/pages/Document/DocumentPage.jsx
+++ b/frontend/src/pages/Document/DocumentPage.jsx
@@ -1,7 +1,7 @@
 import { useState, useEffect, useRef, useMemo } from 'react'
 import { useParams, useNavigate, useSearchParams } from 'react-router-dom'
 import { Layout, Menu, Spin, FloatButton, Button, Tooltip, message, Anchor, Modal, Input, Switch, Space, Dropdown, Empty } from 'antd'
-import { EditOutlined, VerticalAlignTopOutlined, ShareAltOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, CopyOutlined, LockOutlined, CloudDownloadOutlined, CloudUploadOutlined, DownOutlined, SearchOutlined, CloseOutlined } from '@ant-design/icons'
+import { EditOutlined, VerticalAlignTopOutlined, ShareAltOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, CopyOutlined, LockOutlined, CloudDownloadOutlined, CloudUploadOutlined, DownOutlined, SearchOutlined, CloseOutlined, MenuOutlined } from '@ant-design/icons'
 import ReactMarkdown from 'react-markdown'
 import remarkGfm from 'remark-gfm'
 import rehypeRaw from 'rehype-raw'
@@ -10,11 +10,12 @@ import rehypeHighlight from 'rehype-highlight'
 import 'highlight.js/styles/github.css'
 import Highlighter from 'react-highlight-words'
 import GithubSlugger from 'github-slugger'
-import { getProjectTree, getFileContent, getDocumentUrl } from '@/api/file'
+import { getProjectTree, getFileContent, getDocumentUrl, getExportPdfUrl } from '@/api/file'
 import { gitPull, gitPush, getGitRepos } from '@/api/project'
 import { getProjectShareInfo, updateShareSettings } from '@/api/share'
 import { searchDocuments } from '@/api/search'
 import VirtualPDFViewer from '@/components/PDFViewer/VirtualPDFViewer'
+import DocFloatActions from '@/components/DocFloatActions/DocFloatActions'
 import Toast from '@/components/Toast/Toast'
 import './DocumentPage.css'
 
@@ -866,16 +867,19 @@ function DocumentPage() {
               )}
             </div>
 
-            {/* 返回顶部按钮 - 仅在markdown模式显示 */}
+            {/* 浮动按钮组 - 仅在markdown模式显示 */}
             {viewMode === 'markdown' && (
-              <FloatButton
-                icon={<VerticalAlignTopOutlined />}
-                type="primary"
-                style={{ right: tocCollapsed ? 24 : 280 }}
-                onClick={() => {
-                  if (contentRef.current) {
-                    contentRef.current.scrollTo({ top: 0, behavior: 'smooth' })
+              <DocFloatActions
+                scrollRef={contentRef}
+                right={tocCollapsed ? 24 : 280}
+                onExportPDF={() => {
+                  if (!selectedFile) return
+                  let url = getExportPdfUrl(projectId, selectedFile)
+                  const token = localStorage.getItem('access_token')
+                  if (token) {
+                    url += `&token=${encodeURIComponent(token)}`
                   }
+                  window.open(url, '_blank')
                 }}
               />
             )}
diff --git a/frontend/src/pages/Preview/PreviewPage.jsx b/frontend/src/pages/Preview/PreviewPage.jsx
index 3366814..65a7403 100644
--- a/frontend/src/pages/Preview/PreviewPage.jsx
+++ b/frontend/src/pages/Preview/PreviewPage.jsx
@@ -1,8 +1,9 @@
 import { useState, useEffect, useRef, useMemo } from 'react'
 import { useParams, useSearchParams, useNavigate } from 'react-router-dom'
-import { Layout, Menu, Spin, FloatButton, Button, Modal, Input, Drawer, Anchor, Empty, Tooltip } from 'antd'
+import { Layout, Menu, Spin, Button, Modal, Input, Drawer, Anchor, Empty, Tooltip } from 'antd'
 import Toast from '@/components/Toast/Toast'
-import { VerticalAlignTopOutlined, MenuOutlined, MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, LockOutlined, SearchOutlined, CloseOutlined, CloudDownloadOutlined } from '@ant-design/icons'
+import DocFloatActions from '@/components/DocFloatActions/DocFloatActions'
+import { MenuFoldOutlined, MenuUnfoldOutlined, FileTextOutlined, FolderOutlined, FilePdfOutlined, LockOutlined, SearchOutlined, CloseOutlined } from '@ant-design/icons'
 import ReactMarkdown from 'react-markdown'
 import remarkGfm from 'remark-gfm'
 import rehypeHighlight from 'rehype-highlight'
@@ -630,29 +631,11 @@ function PreviewPage() {
             </div>
 
             {viewMode === 'markdown' && (
-            <FloatButton.Group
-              trigger="hover"
-              type="primary"
-              icon={<MenuOutlined />}
-              style={{ right: !isMobile && !tocCollapsed ? 280 : 24 }}
-            >
-              <Tooltip title="导出 PDF" placement="left">
-                <FloatButton
-                  icon={<FilePdfOutlined />}
-                  onClick={handleExportPDF}
-                />
-              </Tooltip>
-              <Tooltip title="回到顶部" placement="left">
-                <FloatButton
-                  icon={<VerticalAlignTopOutlined />}
-                  onClick={() => {
-                    if (contentRef.current) {
-                      contentRef.current.scrollTo({ top: 0, behavior: 'smooth' })
-                    }
-                  }}
-                />
-              </Tooltip>
-            </FloatButton.Group>
+              <DocFloatActions
+                scrollRef={contentRef}
+                right={!isMobile && !tocCollapsed ? 280 : 24}
+                onExportPDF={handleExportPDF}
+              />
             )}
           </Content>