A retainer capable of absorbing a positional difference between the moving and placing coordinates set in a moving and placing machine and the axis of a work, thus restraining the work from being defectively moved and placed. The retainer includes: a pillar-like member having a base end portion to stand on a base plate; a narrow portion formed at the center part of the pillar-like member; and a holding portion which is formed at the tip end of the pillar-like member, which is thicker than the narrow portion, and which is arranged to fit the cylindrical inner peripheral surface of a work.