PURPOSE: To prevent generation of an abnormal noise by providing a cover which covers an opening of a clutch outer whose one end is supported to a driving shaft, arranging the plate between the clutch outer and a clutch inner so as to remain a specified gap, and thereby suppressing eccentricity of the clutch outer.

CONSTITUTION: A stepped part 13b is formed on an front end of outer peripheral part of a clutch outer 13, while a plate 22 is arranged between the stepped part 13b and a groove 15c of a clutch inner. 15 so as to remain a specified gap g3 and fined by means of a cover 10. In such an over-running clutch device 100 constructed as above, the clutch outer 12 and the clutch inner 15 are supported in the gap g3 by means of the plate 22, so that the eccentricity of the clutch outer 10 is prevented even if the clutch outer 13 is disengaged from the clutch inner 15 under an over-running condition. An abnormal noise is prevented from generating under an over-running condition.