html

<div id="box">
   ![](images/1.png)
</div>

css

#box{
    width: 700px;
    height: 500px;
    line-height:500px;
    font-size: 0;
    text-align: center;
    vertical-align: middle;
    border:1px solid red;
}
img{
    vertical-align: middle;
}