<div id="content">

  <h1>html</h1>

  <h1>php</h1>

  <h1>javascript</h1>

  <h1>jquery</h1>

  <h1>java</h1>

</div>

<script type="text/javascript">

function clearText() {

  var content=document.getElementById("content");

  var nameH1=content.getElementsByTagName("h1");

  for(var i=0;i<nameH1.length;i++){

  //for(var i=nameH1.length-1;i>=0;i--){

     content.removeChild(nameH1[i]);        

   }

}

</script>

<button onclick="clearText()">清除节点内容</button>