diff --git a/web-to-ppt/background.js b/web-to-ppt/background.js
index 96fec62..fc8e77b 100644
--- a/web-to-ppt/background.js
+++ b/web-to-ppt/background.js
@@ -259,6 +259,18 @@ chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
     return true;
   }
 
+  // 下载 PPTX（由 popup 调用，background 执行下载）
+  if (message?.type === "WEB_TO_PPT_DOWNLOAD") {
+    (async () => {
+      const dataUrl = 'data:application/vnd.openxmlformats-officedocument.presentationml.presentation;base64,' + message.base64;
+      await chrome.downloads.download({ url: dataUrl, filename: message.filename });
+      return { ok: true };
+    })()
+      .then(sendResponse)
+      .catch(error => sendResponse({ ok: false, error: error.message || String(error) }));
+    return true;
+  }
+
   return false;
 });
 
diff --git a/web-to-ppt/popup.js b/web-to-ppt/popup.js
index 0a0f24f..008fcd0 100644
--- a/web-to-ppt/popup.js
+++ b/web-to-ppt/popup.js
@@ -101,25 +101,31 @@ async function exportPptx() {
       setProgress(50 + Math.min(40, Math.floor(Math.random() * 40)), msg);
     });
 
-    // 4. 生成 PPTX
+    // 4. 生成 PPTX 并通过 background 下载
     setProgress(90, '正在打包...');
     const blob = await WebToPPT.schemaToPptxBlob(schema);
-
-    // 5. 下载（用 data URL，和原插件一致）
-    setProgress(95, '正在下载...');
     const buffer = await blob.arrayBuffer();
     const bytes = new Uint8Array(buffer);
     let binary = '';
     for (let i = 0; i < bytes.length; i += 0x8000) {
       binary += String.fromCharCode(...bytes.subarray(i, i + 0x8000));
     }
-    const dataUrl = 'data:application/vnd.openxmlformats-officedocument.presentationml.presentation;base64,' + btoa(binary);
+    const base64 = btoa(binary);
 
+    // 5. 让 background 执行下载
+    setProgress(95, '正在下载...');
     const title = jsonData.source?.title || 'webpage';
     const safeTitle = title.replace(/[\\/:*?"<>|]+/g, '-').replace(/\s+/g, '-').slice(0, 64) || 'webpage';
     const filename = `web-to-ppt/${safeTitle}-${Date.now()}.pptx`;
 
-    await chrome.downloads.download({ url: dataUrl, filename });
+    const dlResult = await chrome.runtime.sendMessage({
+      type: 'WEB_TO_PPT_DOWNLOAD',
+      base64,
+      filename
+    });
+    if (!dlResult || !dlResult.ok) {
+      throw new Error(dlResult?.error || '下载失败');
+    }
 
     setProgress(100, `已导出：${filename}`);
     setResult('success', '导出完成');