Parallel vector buffer analysis approaches can be classified into 2 types:algorithm-oriented par-allel strategy and the data-oriented parallel strategy. These methods do not take its applicability on the existing geographic information systems( GIS) platforms into consideration. In order to address the problem, a spatial decomposition approach for accelerating buffer analysis of vector data is pro-posed. The relationship between the number of vertices of each feature and the buffer analysis com-puting time is analyzed to generate computational intensity transformation functions ( CITFs) . Then, computational intensity grids ( CIGs) of polyline and polygon are constructed based on the relative CITFs. Using the corresponding CIGs, a spatial decomposition method for parallel buffer analysis is developed. Based on the computational intensity of the features and the sub-domains generated in the decomposition, the features are averagely assigned within the sub-domains into parallel buffer analysis tasks for load balance. Compared with typical regular domain decomposition methods, the new approach accomplishes greater balanced decomposition of computational intensity for parallel buffer analysis and achieves near-linear speedups.