Abstract: In this paper, we use the numerical model to perform the real-time rainfall forecast with GMS satellite data in Zishui River Basin from 15 May to 15 August in 2001.We also carry out numerical simulations of ten heavy rainfall cases in Huaihe River Basin with the TMI (Tropical Rainfall Measuring Mission TRMM) Microwave Imager data incorporated into the PSU/NCAR meso-scale model MM5 and use the data obtained by the TMI to change the distribution of rain water in the model.The results show that, for all floods caused by heavy rainfall events occurred in these 3 months in Zishui River Basin, our forecasts agree well with the observations.It provides the important reference for controlling flood beforehand Taking the Huaihe River Basin for example, since the TMI data can reflect meso-scale weather system with high resolution, the predicted rainfall distributions agree with the observations and the accuracy of predicting the threat score of ten heavy rainfall is higher than that without using the TMI data.