Abstract: In a shift device for an automatic transmission, notches, which are adapted to be engaged by a roller mounted to a detent spring, is defined in an upper surface of a shift restraining plate secured to a base plate, and a surface of a recess defined in an inner surface of the shift restraining plate is formed into a restraining cam surface which is adapted to be engaged by a lock pin. Mounted to an outer surface of the shift restraining plate are a shift lock mechanism for retaining the lock pin in a parking position maintaining groove in the restraining cam surface, and a forcedly-lock-releasing mechanism capable of releasing the operation of the shift lock mechanism by a manual operation. The shift restraining plate is commonly used for a detent mechanism for resiliently retaining a shift lever at any of a plurality of shift positions, and a shift restraining mechanism for restraining the shift position of the shift lever.