Abstract: A one-way bearing includes inner and outer races and balls and springs set between the races. The outer race defines accommodation chambers that respectively receives balls and springs therein in a movable manner and is composed of first and second compartments. The first compartment has a front wall surface from which a bottom wall surface extends in a radially outward direction at a given angle. The bottom wall surface extends a distance where an inward raised step is formed and connected to the second compartment. The second compartment includes a recessed space and has a configuration that includes a flange radially inboard the recessed space, and has an internal wall facing the front wall surface. The spring is retained in the second compartment for holding the ball against the front wall surface of the first compartment and the inner race to form a constraining engagement.