diff --git a/lib/wechat.js b/lib/wechat.js
index a6c428ee..4ed35894 100644
--- a/lib/wechat.js
+++ b/lib/wechat.js
@@ -56,7 +56,9 @@ var tpl = ['<xml>',
       '<Description><![CDATA[<%-content.description%>]]></Description>',
       '<MusicUrl><![CDATA[<%-content.musicUrl || content.url %>]]></MusicUrl>',
       '<HQMusicUrl><![CDATA[<%-content.hqMusicUrl || content.hqUrl %>]]></HQMusicUrl>',
+      '<%if (content.thumbMediaId) {%> ',
       '<ThumbMediaId><![CDATA[<%-content.thumbMediaId || content.mediaId %>]]></ThumbMediaId>',
+      '<%}%>',
     '</Music>',
   '<% } else if (msgType === "voice") { %>',
     '<Voice>',