Abstract: As to four heavy rainstorm processes, numeric experiments of Grell and Kuo cumulus convection parameterization schemes and their composition have been done by using MM5 meso-scale model, and simulating abilities for forecasting precipitation have been analysed.The results show that there are some difference in precipitation areas, precipitation intensity, precipitation evolution and its properties different experiment schemes.Precipitation intensity and distribution of finer net grid area depends on cumulus parameterization scheme used in the area.The precipitation area simulated by using Kuo scheme is moving less, the main precipitation avea appears more in west and south avea.precipitation intensity is weaker.The results using Grell scheme in two integral areas are almost similar to that of composition experiment using Kuo scheme in coarser area and Grell scheme in finer area.Two experiment schemes have abilities to forecast eastern moving of precipitation areas, and precipitation intensities are more closed to real-time precipitation.Convectively precipitation is mainly when using Kuo scheme.Convectively and non-convectively precipitation are in proportion in total precipitation when using Grell scheme, which maybe reflect real precipitation better.Process analysis combined statistic checks show that simulating results using Grell scheme in two integral areas are better.At the same time, it is obvious there is no perfect convection parameterization scheme.Developing convection parameterization scheme with regional characteristic has an important and actual meaning.