diff --git a/lib/api_media.js b/lib/api_media.js
index a0a4df80..841be999 100644
--- a/lib/api_media.js
+++ b/lib/api_media.js
@@ -92,7 +92,10 @@ exports.getMedia = function (mediaId, callback) {
 exports._getMedia = function (mediaId, callback) {
   var url = this.fileServerPrefix + 'media/get?access_token=' + this.token.accessToken + '&media_id=' + mediaId;
   urllib.request(url, {}, wrapper(function (err, data, res) {
-    // 不用处理err，因为wrapper函数处理过
+    // handle some err
+    if (err) {
+      return callback(err);
+    }
     var contentType = res.headers['content-type'];
     if (contentType === 'application/json') {
       var ret;