In a vehicle, a pair of left and right drive wheels are linked with a steering input device so that the drive wheels are turned in accordance with a driver's steering input force input by a driver to the steering input device. In this course, a steering assistance force is added to the driver's steering input force. Driving forces to be applied to the drive wheels are individually controlled in accordance with a running condition of the vehicle. A steering reaction force is calculated which originates from a difference in the driving forces between the drive wheels and acts on the steering input device. The steering assistance force added to the driver's steering input force is increased or decreased so as to compensate the steering reaction force.