A sustained anomalous heavy rainfall event occurred over southern Hubei Province during 20—22 July 1998. A two-way nested nonhydrostatic mesoscale numerical model called MM5 was conducted to simulate the event. The simulative results show that the rain-band distribution with its center is basically consistent with that of the observation, especially for the results derived from the fine nested simulation that are very closely with the observations. In addition, the mesoscale system connecting with the heavy rainfall occurred in 20—22 July is simulated successfully.