To reliably prevent troubles in motor drive or the like caused by biting of foreign matters as a seat is moved, to ensure an occupant walk-in space, a cargo space in an automobile, or the like, and to reliably adjust a series of motions of the entire seat including a rear seat.

A load detection sensor to detect the load of a reversible motor is provided. When an abnormal load is detected as a seat is brought close thereto, the movement of the seat is stopped once, and the seat is returned to the position where no abnormal load is detected to control the seat to be completely stopped. When an abnormal load is detected as a seat cushion is sprung up, the spring-up of the seat cushion is once stopped, and returned to the original seating position to control the seat cushion to be completely stopped.