An ECU executes steering control in a vehicle including an electronic control power steering apparatus. In the steering control, it is determined that an assist motor is in a power generating state when a motor rotation speed ω which is the rotation speed of the assist motor is greater than an upper limit rotation speed ω1 set according to a motor command voltage Vq that is the driving voltage of the assist motor. When the assist motor is in the power generating state, the ECU interrupts the supply of current to the assist motor by controlling a relay portion of a drive apparatus that drives the assist motor so that it is open, thereby reducing the amount of power that is generated to zero. Also, when returning to an assist possible state, assist torque Tm is changed gradually with zero as the initial value in order to prevent it from changing suddenly.