17 cloud microphysics parameterization schemes of the weather research and forecasting modeling system(WRF v3.5.1 version) are used to simulate the torrential rain event over Beijing on July 21-22, 2012. Results show that is terms of the simulation effects on precipitation of different levels each microphysical parameterization scheme has its advantage. The NSSL 1-momlfo scheme well simulates the moderate and torrential rainfall, in particular, the location and intensity of the rainfall agree well with observations. The Eta(Ferrier) and kessler schemes simulate the heavy rain best. Overall, the successful simulation schemes on this torrential rainfall are NSSL 1-mom, NSSL 1-momlfo and Milbrandt 2-mom schemes, while the WDM6 scheme performs worst. In addition, when the mentioned above "good schemes" are used, the simulated variations of cloud water, cloud liquid water, cloud ice and graupel are consistent with those of the observed precipitation. For these "good schemes", the WRF model also simulates much more ice particles and wider of range super-cooled water, which are able to promote the development of ice-phase process, finally leading to more precipitation.