To improve an operation property by controlling a driving unit with change of a prescribed setting value in order to reduce a drag torque when an instability occurs on at least one driving wheel, in the case where the drag torque of an internal combustion engine is controlled on the basis of a wheel speed signal.

During operation of a vehicle, in a control unit 12, a signal expressing wheel speed of each wheel is inputted from measuring devices 20 to 24, and a target value of a torque of a driving unit is generated on the basis of each wheel speed signal. The target value is transmitted to a first control unit 10 through communication lines 25, 26, an electric operation type throttle valve is controlled for controlling an air supplying rate of the target value, an ignition angle is controlled, and/or the fuel supplying rate is controlled. In this case, a target sliding value and real sliding value of each wheel are calculated. When it is judged that a vehicle is apt to be unstably, a drag torque is controlled by change of a second setting value for controlling the ignition angle and the fuel supplying rate.