Abstract: To protect the water environment of the Three Gorges Reservoir(TGR),it is very inportant to predict the change trend of eutrophication of the TGR.This paper mainly introduces an eutrophication model system,which is developed by considering the integration actions,nutrient(including P,N),climate(including temperature and light intensive) and hydrodynamics on the algal growth rate based on the feature of TGR.Takinge the Daning River,a branch largely effected from the storage of TGR,as a case,an empirical formula is presented firstly to describe the effect of hydrodynamics on the algal growth rate in the Daning River.The verification of the formula is conducted with the measurement data from the Daning River.It shows that the formula can simulate better the general feature of the algal growing and decaying in the Daning River after the storages water in TGR.