Assimilation of ATOVS(Advanced TIROS Operational Vertical Sounder) microwave radiance data is implemented in WRF-EnSRF(Weather Research and Forecasting-Ensemble Square-Root Filter) system to test its capacity of satellite data assimilation and its simulation performance in a rainstorm.The ATOVS data assimilation experiment and the control experiment are performed to simulate a rainstorm process in Guangdong region on 6-7 June 2008.Results show that,assimilating the radiance data,it can enrich temperature information in the upper troposphere and humidity information in the mid-lower troposphere,and improve initial wind field.Both experiments have well simulated the main rainfall area and period,but the simulations of the rain storm and large rain storm in the control experiment are not good enough.In contrast,the assimilation experiment can improve the simulations of location,intensity and range of the strong precipitation center,which is more accordant with the observed precipitation.