An operation torque estimating portion estimates an operation torque Th of a driver based on an input angle θh and an input torque T output from a torque sensor. A non-holding state detecting portion determines whether the driver is holding a steering wheel by comparing an absolute value of the operation torque Th and a predetermined value ε1. An equilibrium detecting portion determines whether an equilibrium point is reached by comparing the absolute value of the input torque T with a predetermined value ε2. When it is determined that the driver is not holding the steering wheel and the equilibrium point is reached, a switching portion switches to such a position that causes a target steering adjusting portion to multiply a target output angle θpm by a predetermined gain G according to the input torque T so that the target steering angle is made smaller.