PURPOSE: To eliminate a feeling of dragging in time of operation, by making up an actuator roller into a barrel type at a point of contact between the actuator roller of a parking lock and a parking hole's cam surface.

CONSTITUTION: With operation for a parking range, a manual plate 14 comes to a turning position where a roller 20 fits a notch. A lever 7 is turned round via a parking rod 13. An actuator roller 9 goes down as being rotated along a copying surface 10a of a parking support 10, pressing a cam surface 2b of a parking pole 2, and a claw part 2a enter in a space between teeth of a parking gear 1 and locked for parking. With the form of the actuator roller 9 made up into a barrel type, abnormally large frictional force is in no case produced in time of operation of a parking lock, thus smooth operation with no feeling of dragging comes possible to be done.