Edit in JSFiddle

<div id="content">
    <div>
       test  
    </div>         
</div>    

#content {
    width:30%;
    height:200px;
    border:1px solid #000000;
    padding:5px;    
    text-align:center;
    display:table;    
}
#content div {
    display: table-cell;
    vertical-align:middle;    
}