The mathematic models of electric power steering system were analyzed and the simulation model based on Matlab/Simulink was built. Two layers control strategies were proposed, which are top layer control strategy and bottom layer control strategy. The top layer control strategy calculates the target current by the methods of basic assist control and compensation control, and the bottom layer control strategy regulates the actual current to track the target current by the PID controller. The simulation results showed that the problems of steering easiness and road feel were solved, the steering dynamic effect was improved, and the return ability was increased.