Abstract: DBSCAN is an outstanding representative of clustering algorithms for its good performance in clustering spatial data.To improve its efficiency this paper proposes GbDBSCAN（Grid based DBSCAN）.GbDBSCAN adopts gird and data binning technique to query density reachable objects for all objects in dataset.It can also identify and handle border points.Experiment results show that GbDBSCAN is much more efficient than DBSCAN in low dimensional data space，without lowering the quality of DBSCAN.