The present invention provides a one-way clutch comprising an outer race, an inner race, a roller adapted to transmit torque between the outer race and the inner race, a cage having a window for holding the roller, a spring disposed in the pocket and adapted to bias the roller toward an engagement direction with respect to the cam surface, and a side plate provided at its inner diameter portion with spline grooves into which a crankshaft of an engine is fitted, and wherein the side plate is secured to the outer race by inserting rivets into through holes provided in the outer race and through holes provided in the side plate and by caulking the rivets.