SOURCE

function initialize() {  
  var map = new BMap.Map("container");
  // 创建地图实例  
  var point = new BMap.Point(121.5097199, 31.2425584);
  // 创建点坐标  
  map.centerAndZoom(point, 15);
  // 初始化地图，设置中心点坐标和地图级别 
  map.addControl(new BMap.NavigationControl({type: BMAP_NAVIGATION_CONTROL_SMALL}));
  //map.setCurrentCity("上海");
  map.addControl(new BMap.OverviewMapControl());
  map.addControl(new BMap.MapTypeControl());
  //map.setCurrentCity("北京");
  map.addControl(new BMap.GeolocationControl({offset: new BMap.Size(10, 60)}));
  var marker = new BMap.Marker(point);        // 创建标注    
	map.addOverlay(marker);                     // 将标注添加到地图中 
  //marker.setAnimation(BMAP_ANIMATION_BOUNCE); //跳动的动画
  var circle = new BMap.Circle(point,500,{strokeColor:"blue", strokeWeight:2, strokeOpacity:0.3}); //创建圆
  map.addOverlay(circle); 
}  
window.onload = initialize; 

<script type="text/javascript" src="http://api.map.baidu.com/api?v=3.0&ak=je9h7EOx3mZk3HwLOUZBRr59yGpYUvY1"></script>

<div id="container"></div> 

html {
  height:100%
}
body{
  height:100%;
  margin:0px;
  padding:0px
}
#container{
  height:600px;
  width: 800px;
  margin-top: 50px;
  margin-left: 50px;
}