The quantitative evaluation of soil erosion is of great importance for the rational land utilization and environment protection in the typical loess hilly region with a serious soil erosion and vulnerable ecological environment.This paper applied AnnAGNPS model which based on process to simulate the soil erosion in Chakou watershed. The applicability of model was validated by using the measured data of runoff and sediment load of five storms.The results indicated that AnnAGNPS model can better simulate surface runoff, the relative error of runoff is from -21.46% to 2.26% (R2=0.99, E=0.99). While the simulation accuracy of the model to sediment is low. The results indicated that the most serious soil erosion of sediment volume per unit area occurred in slope cropland, especially the slope cropland with the walnut trees and corn.