To provide a pulley unit capable of stabilizing the motion of the clutch for a long time when a one-way clutch is mounted.

The one-way clutch 20 is mounted between a pulley 10 and a shaft body 12 which are disposed coaxially. The one-way clutch 20 comprises a U-shaped inner ring 22 integrated with the pulley 10, a U-shaped outer ring 24 integrated with the shaft body 12, and a roller 26 stored in a wedge-shaped space formed between the inner ring 22 and the outer ring 24. The load applied from a belt 90 acts not on the one-way clutch 20 but mostly on a bearing 30 disposed on the inner side of the clutch in the radial direction.