A control unit controls an electric motor based on position data on a window glass, and controls an opening-closing operation of the window glass. The control unit includes a reverse rotation detector which detects a reverse rotation operation of the window glass, a reverse rotation prevention controller which performs reverse rotation prevention processing of the electric motor when a reverse rotation is detected, and a position data correction unit which corrects position data on the window glass in an initial operation after occurrence of a reverse rotation operation. If a pulse signal associated with rotation of the electric motor is not input in an initial operation after the detection of the reverse rotation operation, the position data correction unit determines that the window glass has reached a top dead center position, stops the motor, and corrects the position data with the position data at that time as an origin position.