Through the statistically analyzing the typical atmospheric circulation and major effect systems of 31 regional rainstorm cases occurred in Chongqing,the major results can be summarized as:(1) the mountain torrential disasters in Chongqing mainly come from landslides,local mud-rock flow and flood in the brooks produced by the heavy precipitation;(2) the typical local storm mainly occurs from May to September,and the most cases happen in July;(3) befor the occurrence of the most rainstorm,the patterns of two ridges with one trough(occupying 52% in the total cases) or two troughs with one ridge(occupying 42% in the total cases) are located in the high latitude;(4) plateau trough(plateau shear),plateau eddy,subtropical high,southwest eddy,low-level jet and surface cold front,et al.,are the major effect systems.