Edit in JSFiddle

.box{
    margin:40px;
    border-radius:1000px;
    -moz-border-radius: 1000px;
    -webkit-border-radius: 1000px;
    width:280px;
    height:280px;
    overflow:hidden;
}

<div class="box">
    <img src="http://uploads.striking.ly/page/images/custom/21302.png?1352375144">
</div>