A centrifugal clutch apparatus can include a driving-side rotational member rotatable around a shaft member connected to a driving device; clutch devices mounted on the driving-side rotational member and movable radially-outward of the driving-side rotational member. A driven-side rotational member rotatable independent from the driving-side rotational member can be arranged for covering the driving-side rotational member and can have an inner circumferential surface to engage with the clutch devices. Friction members can be adapted to be abutted against the inner circumferential surface so as to transmit the driving power of the driving device to the driven-side rotational member. The inner circumferential surface of the driven-side rotational member can be formed with a groove and a tensioning member formed as a ring-shaped member can be snap-fitted into the groove and held therein under a radially-outward biasing force.