The EPS model and ASS model of an automobile was built respectively. Considering the mutual influences between EPS and ASS systems, an integrated control structure was designed. On one hand, considering the comfort and handling stability characteristics, the frequency-dependent weighting matrices were introduced. In order to reduce the vibration at specific bands of frequency, a H∞ controller was designed. On the other hand, a PID controller for the EPS was also designed to improve steering performance. Simulation results show that integrated control scheme is effective, the comfort and handling stability and other characteristics can be greatly improved.