diff --git a/backend/app/export/markdown.py b/backend/app/export/markdown.py
index 436ebda..7f83986 100644
--- a/backend/app/export/markdown.py
+++ b/backend/app/export/markdown.py
@@ -178,6 +178,8 @@ class _AstMapper:
                 type="link", node_id=self.next_id(), attributes=attributes,
                 children=self.map_inline(token.get("children", [])),
             )
+        if kind == "inline_html":
+            return DocumentNode(type="text", node_id=self.next_id(), text=token.get("raw", ""), attributes={"raw_html": True})
         if kind == "codespan":
             return DocumentNode(type="codespan", node_id=self.next_id(), text=token.get("raw", ""))
         if kind == "image":
diff --git a/backend/app/export/service.py b/backend/app/export/service.py
index e001bcc..70c351a 100644
--- a/backend/app/export/service.py
+++ b/backend/app/export/service.py
@@ -411,12 +411,23 @@ async def preview_resources(request: ExportRequest):
     from app.export.assets import enrich_document
     from app.plot.parser import parse_source
     from app.plot.render import render_svg
-    from app.export.document import Document
+    from app.export.document import Document, DocumentNode
+    from html.parser import HTMLParser
     markdown, _, metadata = await _resolve_source(request.source, True)
     def prepare():
         document = parse_document(markdown)
         images, plots = [], []
+        class HtmlImages(HTMLParser):
+            def handle_starttag(self, tag, attrs):
+                if tag == 'img':
+                    src = dict(attrs).get('src')
+                    if src:
+                        visit(DocumentNode(type='image', node_id='html-image', attributes={'src':src}))
         def visit(node):
+            if node.type == 'html_block' or node.attributes.get('raw_html'):
+                parser = HtmlImages(convert_charrefs=True)
+                parser.feed(node.text)
+                parser.close()
             if node.type == 'image':
                 warnings = enrich_document(Document(node_id='pdf-resources', children=[node]), (metadata or {}).get('file_path'), True, request.options, preserve_alpha=True)
                 raw = node.attributes.get('static_png')
diff --git a/backend/tests/test_pdf_browser.py b/backend/tests/test_pdf_browser.py
index 1a42030..531a8fb 100644
--- a/backend/tests/test_pdf_browser.py
+++ b/backend/tests/test_pdf_browser.py
@@ -45,3 +45,25 @@ def test_browser_prints_css_without_executing_document_scripts(tmp_path):
         text=subprocess.check_output(['pdftotext',str(pdf),'-']).decode('utf-8')
         assert 'Theme Snapshot' in text
         assert 'EXECUTED' not in text
+
+
+@pytest.mark.parametrize('source', ['<div><IMG SRC="assets/a&amp;b.png"></div>', 'inline <img src="assets/a&amp;b.png"/> image'])
+def test_preview_embeds_html_images(source):
+    from app.config import get_settings
+    from PIL import Image
+    import base64
+    folder=get_settings().vault_path/'notes'/'assets'
+    folder.mkdir(parents=True)
+    Image.new('RGBA',(2,2),(10,20,30,128)).save(folder/'a&b.png')
+    resources=asyncio.run(service.preview_resources(ExportRequest(format='pdf',source={'type':'markdown','markdown':source,'file_path':'notes/test.md'})))
+    image=resources['images'][0]
+    assert image['source']=='assets/a&b.png'
+    assert base64.b64decode(image['data'].split(',')[1]).startswith(b'\x89PNG')
+    assert image['warnings']==[]
+
+
+def test_html_images_keep_path_validation_and_code_is_not_an_image():
+    source='<img src="../../private.png">\n\ninline <img src="https://example.com/a.png">\n\n`<img src="code.png">`\n\n```html\n<img src="fenced.png">\n```'
+    resources=asyncio.run(service.preview_resources(ExportRequest(format='pdf',source={'type':'markdown','markdown':source})))
+    assert [image['source'] for image in resources['images']]==['../../private.png','https://example.com/a.png']
+    assert all(image['data'] is None and image['warnings'] for image in resources['images'])
diff --git a/frontend/src/services/pdfSnapshotService.spec.ts b/frontend/src/services/pdfSnapshotService.spec.ts
index a454943..2025e3b 100644
--- a/frontend/src/services/pdfSnapshotService.spec.ts
+++ b/frontend/src/services/pdfSnapshotService.spec.ts
@@ -58,3 +58,19 @@ it('does not invent a metadata bar for plain notes or unsupported frontmatter',a
   expect(renderMarkdown).toHaveBeenCalledWith(source,expect.anything())
  }
 })
+
+it('exports metadata-only notes without submitting an empty resource request',async()=>{
+ for(const tail of ['', '\n  \n']) {
+  const html=await preparePdfSnapshot('---\ntitle: Metadata only\ntags: [draft]\n---\n'+tail,'note',{theme_id:'light',include_title:false,page_size:'A4'})
+  const doc=new DOMParser().parseFromString(html,'text/html')
+  expect(doc.querySelector('.note-metadata h1')?.textContent).toBe('Metadata only')
+  expect(doc.querySelector('.metadata-tag')?.textContent).toBe('draft')
+ }
+ expect(apiClient.post).not.toHaveBeenCalled()
+})
+it('embeds prepared HTML images without retaining local URLs',async()=>{
+ vi.mocked(renderMarkdown).mockResolvedValueOnce('<p><img src="assets/a&amp;b.png"></p>')
+ vi.mocked(apiClient.post).mockResolvedValueOnce({images:[{source:'assets/a&b.png',data:'data:image/png;base64,aGVsbG8=',warnings:[]}],plots:[]})
+ const html=await preparePdfSnapshot('<img src="assets/a&amp;b.png">','note',{theme_id:'light',include_title:false,page_size:'A4'})
+ expect(new DOMParser().parseFromString(html,'text/html').querySelector('img')?.getAttribute('src')).toBe('data:image/png;base64,aGVsbG8=')
+})
diff --git a/frontend/src/services/pdfSnapshotService.ts b/frontend/src/services/pdfSnapshotService.ts
index 61213f6..e7a1284 100644
--- a/frontend/src/services/pdfSnapshotService.ts
+++ b/frontend/src/services/pdfSnapshotService.ts
@@ -78,7 +78,7 @@ export async function preparePdfSnapshot(markdown:string,title:string,options:Op
   const scope=scopeAttributes(VisualMarkdownEditor)
   // Match the editor DOM and scoped styles, with read-only metadata controls.
   const metadataHtml=metadata ? `<section class="note-metadata"${scope} aria-label="${escape(t('笔记属性','Note properties'))}"><span class="metadata-caption"${scope}>${escape(t('笔记属性','Note properties'))}</span>${metadata.title ? `<h1${scope}>${escape(metadata.title)}</h1>` : ''}<div class="metadata-tags"${scope}><span class="metadata-label"${scope}>${escape(t('标签','Tags'))}</span>${metadata.tags.map(tag=>`<span class="metadata-tag"${scope}><span${scope}>${escape(tag)}</span></span>`).join('')}</div></section>` : ''
-  const resources=await apiClient.post<Resources>('/api/exports/preview-resources',{format:'pdf',source:{type:'markdown',markdown:body,file_path:filePath},options})
+  const resources:Resources=body.trim() ? await apiClient.post<Resources>('/api/exports/preview-resources',{format:'pdf',source:{type:'markdown',markdown:body,file_path:filePath},options}) : {images:[],plots:[]}
   signal?.throwIfAborted()
   const rendered=await renderMarkdown(body,{themeId:options.theme_id,theme:dark?'dark':'light',preferences,pdf:{mermaidVariables:diagramVariables,plot:async source=>{
     const plot=resources.plots.find(p=>p.source.trim()===source.trim()); if(!plot?.svg)throw Error(plot?.warnings.join('; ')||'函数图像无法导出');return plot