The turning amount of a turning unit is controlled according to the steering amount of a steering unit mechanically uncoupled from the turning unit. A steering reaction force characteristic such that the larger the self-aligning torque, the larger the steering reaction force is set on coordinates with the self-aligning torque and the steering reaction force as coordinate axes. When a steering reaction force corresponding to the self-aligning torque is applied to the steering unit based on the steering reaction force characteristic, the steering reaction force characteristic is offset on the coordinates in such a direction that the larger the integral value of a yaw angle, the larger the absolute value of the steering reaction force, the yaw angle being an angle formed by a white line and a traveling direction of an own vehicle.