/** 
     * 计算两点之间距离 
     * @param start 
     * @param end 
     * @return 米 
     */  
    public double getDistance(LatLng start,LatLng end){  
        double lat1 = (Math.PI/180)*start.latitude;  
        double lat2 = (Math.PI/180)*end.latitude;  
          
        double lon1 = (Math.PI/180)*start.longitude;  
        double lon2 = (Math.PI/180)*end.longitude;  
          
//      double Lat1r = (Math.PI/180)*(gp1.getLatitudeE6()/1E6);  
//      double Lat2r = (Math.PI/180)*(gp2.getLatitudeE6()/1E6);  
//      double Lon1r = (Math.PI/180)*(gp1.getLongitudeE6()/1E6);  
//      double Lon2r = (Math.PI/180)*(gp2.getLongitudeE6()/1E6);  
          
        //地球半径  
        double R = 6371;  
          
        //两点间距离 km，如果想要米的话，结果*1000就可以了  
        double d =  Math.acos(Math.sin(lat1)*Math.sin(lat2)+Math.cos(lat1)*Math.cos(lat2)*Math.cos(lon2-lon1))*R;  
          
        return d*1000;  
    }  

LatLng start = new LatLng(39.95676, 116.401394);  
LatLng end = new LatLng(36.63014,114.499574);  
getDistance(start, end);