Abstract: The circulation situation, the water vapor transport characteristics, and cloud physical mechanism of precipitation during the vortex rainstorm process in Chongqing province from June 30 to July 1, 2016 were studied based on the FNL reanalysis data and the high resolution data from the mesoscale numerical mode.The results show that affected by the 500hPa short wave trough and 700hPa vortex,and the continuous transportation of warm water vapor from the Bay of Bengal and the South China Sea,it provides favorable conditions for the occurrence and development of this vortex raintorm; the contribution of the water vapor flux from the southern boundary to the whole rainstorm process is the largest,followed by that from the eastern boundary.In addition,there are significant differences in cloud physical precipitation mechanisms in different regions and periods of precipitation development.The pre- and post-precipitation in western Chongqing is mixed-phase precipitation; the cloud system in the pre-precipitation of northeast Chongqing is mainly cold cloud,and the latter is mainly warm cloud precipitation.