The estimation of steering characteristics such as steer feeling by using only computer simulation technology is extremely difficult. In this paper, to solve this problem, we consider the reproduction of behavior of steering wheel and the control method with developed computer simulation and steering simulator when the road surface condition changed suddenly. Considering the sudden change of the road surface condition to be disturbance, the disturbance compensator for suppression control is designed. In addition, we propose a controller design procedure for electric power steering (EPS) systems to develop the control method efficiently. First, we analyze the behavior by steering simulator or actual car and construct the human model for the computer simulation of EPS systems. Next, we design outline of the disturbance compensator by the computer simulation using the human model. The disturbance compensator is also designed in detail with experiments of the steering simulator, and it will be designed finally by experiments of the actual car.