SOURCE

var oBox = document.querySelector("#box");
document.onmousemove = function(e){
  event = e || window.event;
  oBox.style.left = event.clientX-oBox.clientWidth/2 + "px";
  oBox.style.top = event.clientY-oBox.clientHeight/2 + "px";
}

<div id="box">
	<img src="https://ss2.bdstatic.com/70cFvnSh_Q1YnxGkpoWK1HF6hhy/it/u=2572018418,1853624015&fm=21&gp=0.jpg"/>
</div>

body{
  background-color:#FFF;
}
#box{
  position: absolute;
}