A roller clutch arranged to transmit rotation in only one direction includes an outer ring (54), an inner ring (55), a plurality of rollers (56), a retainer (57), a cam surface (54a), and a plurality of spring members (58). The inner ring is disposed on the inner peripheral surface of the outer ring. The rollers are disposed between the inner ring and the outer ring in a circumferential direction and are allowed to frictionally engage the outer and inner rings. The retainer (57) includes a plurality of holding portions (57b) disposed among the rollers, and shaft portions (57c) that protrude from the holding portions (57b) toward the rollers. The cam surface (54a) is an oblique surface on the inner peripheral surface of the outer ring and arranged to contact the outer peripheral surface of the rollers. The spring members (58) are disposed on the outer peripheral side of the shaft portions (57c) and urge the rollers to frictionally engage the cam surface.
