主要代码: position:absolute; top:50%; left:50%; margin-top:-(height/2); margin-left:-(width/2) <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>已知宽高度DIV垂直水平居</title> <style type="text/css"> <!-- .main{ position:absolute; top:50%; left:50%; width:560px; height:188px; margin:-94px 0 0 -280px; background:#C8EDFB} --> </style> </head> <body> <div> <div class="main">已知宽高度DIV垂直水平居</div> </div> </body> </html> 提示:您可以先修改部分代码再运行