Abstract: Left and right driven wheels are connected to a pair of continuously variable transmissions and independently driven. The driven wheels are increased or decreased in speed at the same rotational numbers by operation of a change lever so as to move a vehicle forward or backward. When a steering angle of a steering wheel exceeds a predetermined value, an inner wheel speed during turning of the vehicle is decreased and an outer wheel speed during turning of the vehicle is increased so as to turn the vehicle. If the steering wheel becomes greater than the predetermined value during forward running of the vehicle at a low speed, the inner driving wheels stop and the vehicle does a stationary turn. However, during forward running at a high speed or backward running of the vehicle, even if the steering wheel becomes greater than the predetermined value, the vehicle does not do a stationary turn.