For the release actuators of the electric sliding doors (this device is to electrically release the front and rear latches of the sliding doors), the worm gear may dislodge and become stuck on the worm wheel gear when the actuator is actuated at the time of door opening, because it does not have an appropriate shape, and as a result, the door latch release lever may stay in an release position. If this occurs, the sliding door may not be firmly locked, and in the worst case, it might open while the vehicle is in motion.