A hydraulic unit 30 and an electromagnetic unit 50 are disposed in directions that are orthogonal to each other. The electromagnetic unit 50 is configured such that a solenoid shaft 52 is held (movement of the solenoid shaft 52 toward the right side in the drawing is restricted) when a coil 64 is energized, and such that movement of the solenoid shaft 52 toward the right side in the drawing is allowed during movement of the piston rod 32 when the coil 64 is not energized. When a hydraulic pressure for a piston 38 is reduced with the coil 64 not energized in a parking unlocked state, switching is performed to a parking locked state with a piston rod 32 moved downward in the drawing while moving the solenoid shaft 52 rightward in the drawing through abutment between a roller 48 of a pin 46 of the piston rod 32 and a distal end portion 54 of the solenoid shaft 52.