PURPOSE: To perform rounding with high accuracy and good efficiency without the need for skillfulness by executing buffing on the beveling part provided at the end part in the orthogonal direction with the rolling direction of a rolling face and performing rounding at the corner part of the projecting bar existed on the beveling part.

CONSTITUTION: The outer peripheral face of the body to be worked is subjected to rolling by relatively rolling the body to be worked with its pressing to the rolling face 12 of the rolling die 10 having the rolling face 12 where a lot of projection bars 22 are provided about in parallel. At the manufacturing time of this die 10, buffing is executed with a buff 26 on the beveling parts 18, 20 provided at the end part in the direction orthogonal with the rolling direction of this rolling face 12. Rounding is thus performed on the corner parts 24, 25 of the projection bar 22 existed at the beveling parts 18, 20.