PURPOSE: To improve the steering performance and save fuel consumption by correcting the operation quantity of an actuator based on the speed variation via the generated torque and load torque of an engine.

CONSTITUTION: A proportional unit 5 forms a rack position direction signal by multiplying the speed variation between a preset speed and an estimated speed (g) by a gain F1. A generated torque compensator 6 calculates the generated torque (d) and forms a generated torque compensation signal (c). A load torque compensator 7 calculates the load torque (j) and forms a load torque compensation signal (i). The compensation signals (c), (i) correct the rack position direction signal (a) of the proportional unit 5 to obtain the operation direction signal (b) of an actuator 2. Accordingly, the speed fluctuation can be suppressed, the speed follow-up property can be improved, the steering performance can be improved, and fuel consumption can be saved.