A distributed model for water and energy transfer between soil, plants and atmosphere (Wetspa) is a distributed hydrological model based on GIS. This paper introduces Wetspa model for the flood simulation of Liuxihe River reservoir basin. In combination with DEM, land use and soil data, the framework of Wetspa model based on arcview3.2 for the Liuxihe River reservoir basin is established. The parameters of the model are calibrated with 15 times flood, and the model is further validated with the other 5 times flood. The results show that the model can be adaptable for flood simulation of Liuxihe River reservoir.