Abstract: Based on the sub-models of MIKE 11 model Rainfall-Runoff model(RR model),Hydrodynamic model(HD model),Advection-Diffusion model(AD model),the corresponding three models used for the middle and lower reaches of Hanjiang river are established.Through the coefficients calibration and the model verification,the models receive a better simulation.The diffusing and moving processes of pollutants from the burst water-pollution accidents are timely simulated by using the above established models under the different hydrological status in winter and summer of 2003.These models can quantitatively predict the reaching time and concentrations of pollutants at any places in the middle and lower of Hanjiang river when water-pollution accidents burst out.