Abstract: In this paper, based on the daily precipitation dataset of grid points(0.5°×0.5°) of version 2 during 1961-2018 from China Meteorological Administration and NCEP/NCAR daily reanalysis dataset such as potential height, wind speed, specific humidity and so on, the percentile threshold method is adopted to confirm regional extreme precipitation events of Jiangnan area, and the comprehensive analysis of weather maps are extracted frontal and cyclonic extreme precipitation, and the temporal and spatial distribution and circulation evolution characteristics of those are compared. The results show that: (1) Frontal extreme precipitation is mainly distributed in the spring, while the cyclonic extreme precipitation is mainly distributed in the summer, and the frequency of frontal extreme precipitation is about three times of that of the cyclones.(2) Frontal extreme precipitation is mainly distributed in Wuyi mountain range, Nanling and other higher areas, while the cyclonic type is located in the southeastern coastal region, and places such as Fujian are greatly affected by both types of extreme precipitation.(3) From two days before the occurrence of frontal and cyclonic extreme precipitation to the same day of them, the vertical ascending velocity of airflow increases, and the subtropical high moves to the west. The maximum water vapor convergence center of frontal extreme precipitation dropped from the 850 hPa isobaric surface in Jiangnan area to the surface, while the center of cyclonic extreme precipitation moved from south to north to Jiangnan area. (4) The water vapor required by frontal extreme precipitation mainly comes from the western Pacific Ocean, Indian Ocean and bay of Bengal, and converges in Jiangnan, while the cyclonic water vapor mainly comes from the Indian Ocean, and moves westward with time in a vortex pattern.