$("#voice>div").each(function(i){
this.onmouseover="this.innerHTML='<embed src='bird.mp3' style='display:none' loop='1' autostart=true>'+'<img src='song.gif' name='bird.mp3' width='16' height='16'/>'+this.innerHTML";
 });

用appendto 或者append更清楚明了吧。我也不是很懂，共同学习！

html：
<div id="test">
    <div>first</div>
    <div>second</div>
</div>

js：
<script>
    $(function(){
        $('#test >div').mouseover(function(){
            alert(this.innerHTML);
            this.innerHTML="<embed src='bird.mp3' style='display:none' loop='1' autostart=true>"
                            +"<img src='song.gif' name='bird.mp3' width='16' height='16'/>"
                            +this.innerHTML;
            alert(this.innerHTML);            
        });
    //    "this.innerHTML='<embed src='bird.mp3' style='display:none' loop='1' autostart=true>'+'<img src='song.gif' name='bird.mp3' width='16' height='16'/>'+this.innerHTML";
    });
</script>

楼上的可以，你的可以加个function，不过显得多余
   $("#voice>div").each(function(i){
this.onmouseover=function（）{
this.innerHTML='<embed src='bird.mp3' style='display:none' loop='1' autostart=true>'+'<img src='song.gif' name='bird.mp3' width='16' height='16'/>'+this.innerHTML";}
});

innerHTML可以用$(this).html("str")还可以用实现