Spatial analysis is the core of the space information system and the key function, and also one of evaluation a spatial information system function of the strength of the important index. Buffer analysis is the basic functions of spatial analysis on spatial information system, and is the basis of many space analysis methods. Buffer analysis is to point to identify a geographic entity or space objects on its surrounding of adjacent sex or the effect and in its built around a certain width of the strip area. In this paper, buffer area analysis of the spatial objects and grid theory are explained. On the basis of above, the establishment of grid algorithm of spatial buffer area and its shortage are also discussed. Finally, it makes exploration to the method application of the spatial buffer area analysis and the aspects of port logistics.