In recent years,it becomes more and more common to study the watershed hydrological conditions by use of hydrological model. The paper took the typical watershed of the third subplot of loess plateau hilly and gully region as example based on SWAT and WetSpa Extension model.It also explore the applicability of the two hydrological models in this area by comparing the input data, parameter, and simulation results of the two hydrological models,in order to select suitable hydrological model in the area and provide reference for the improvement of model performance in the future. The calibration and validation for 15 consecutive years indicated that the two models can get better result,but SWAT model can apply in the simulation process of hydrology and sediment,and has a comprehensive function; WetSpa Extension model can only provide the module of hydrological simulation, it has the advantage of random simulation time step and can simulate flood.