<head> <script src="http://apps.bdimg.com/libs/jquery/1.10.2/jquery.min.js"></script> <script> $(function(){ $('#tt').bind('input propertychange', function() { $("#sp").html($(this).val().length); }); }); </script> </head> <body> 字数:<span id='sp'></span><br> <textarea id='tt'></textarea> </body>