At an inner circumferential surface of a cam frame, second cam grooves and an inner gear are formed. A second lens group frame includes a base, extensions each extending from the base in an optical axis direction, and cam pins each outwardly protruding from a tip end part of a corresponding one of the extensions in a radial direction. In the extension, a stepped part is formed. The stepped part overlaps, when each cam pin moves according to a corresponding one of the second cam grooves, with the inner gear as viewed in the radial direction, and is recessed toward the inside in the radial direction as compared to a tooth tip of the inner gear so as not to overlap with the tooth tip of the inner gear as viewed in a circumferential direction.