To prevent a fall of a lock pin from a groove for locking and prevent release from the locked state.

This caster is constituted by a body 1 to be mounted through a oscillating mechanism 11, a wheel 2 arranged rotatably in the body 1, a brake lever 3 supported in the body 1 in capable of oscillation with a lock pin 31 arranged at the tip end, a pin guide 4 formed in the body 1 for guiding the lock pin 31, and a plurality of grooves 5 for wheel lock formed on the inner circumferential wall of the wheel 2 and into which the lock pin 31 is inserted. Opposed faces 51 and 52 of the grooves 5 for wheel lock are formed with being inclined so that the opposing interval gets smaller toward the center of the wheel, and the longitudinal shaft of the brake lever 3 and the opposed faces 51 and 52 of the grooves 5 for wheel lock form an acute angle.