向上滚动：

<div id=demo style="overflow:hidden; width:200px; height:400px;">
<div id=demo1>
<img src="1.png"><br><img src="2.png"><br><img src="3.png"><br>
</div>
<div id=demo2></div>
</div>
<script language="javascript">
var speed=30
demo2.innerHTML=demo1.innerHTML
function Marquee(){
if(demo2.offsetTop-demo.scrollTop<=0)
demo.scrollTop-=demo1.offsetHeight
else{
demo.scrollTop++
}
}
var MyMar=setInterval(Marquee,speed)
demo.onmouseover=function() {clearInterval(MyMar)}
demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}
</script>

向下滚动(替换 js 部分就可以了)：

<div id=demo style="overflow:hidden; width:200px; height:400px;">
<div id=demo1>
<img src="1.png"><br><img src="2.png"><br><img src="3.png"><br>
</div>
<div id=demo2></div>
</div>
</div>
<script language="javascript">
var speed=30
demo2.innerHTML=demo1.innerHTML
demo.scrollTop=demo.scrollHeight
function Marquee(){
if(demo1.offsetTop-demo.scrollTop>=0)
demo.scrollTop+=demo2.offsetHeight
else{
demo.scrollTop--
}
}
var MyMar=setInterval(Marquee,speed)
demo.onmouseover=function() {clearInterval(MyMar)}
demo.onmouseout=function() {MyMar=setInterval(Marquee,speed)}
</script>