PURPOSE: To improve an accuracy by forming numerous unevennesses at the back face inner diameter part of the V-groove part on the outer peripheral face of a metal plate made poly V-pulley therein.

CONSTITUTION: A poly V-pulley is made of one plate and its cylindrical part has numerous V-grooves 2 and at both ends of this cylindrical part, the flange part 4 having the outer diameter larger than that of the V-crest 3 between the V-grooves 2 and the flange part 5 superposed by two sheets exist. The center part from the flange part 5 is a disk, having a center hole 6, Numerous unevennesses are provided on the inner diameter part of the back side of the V-groove 2 and this unevenness is composed of the recessed part 7 and projecting part 8 running in parallel to the axial line A direction. The diameter increase of the center part is thus reduced with the rolling of the case of form rolling being constrained and the angular accuracy is improved as well.