PURPOSE: To continuously form a highly accurate tooth profile uniform in pitch by moving a hoop being a stock intermittently at a feed rate of the same pitch as that of a specified tooth profile and repeating plural stages of press-forming at the same position.

CONSTITUTION: The hoop 1 is fed between an upper and a lower die 2, 3 inter mittently at the same pitch as that of the tooth profile and forming of plural stages is repeated through plural forming recessed and projecting parts so that each tooth depth increases in sequence to the same positions of the hoop 1. In this way, from the shapes of the dies and the shape of the hoop, the hoop is restrained by the dies larger in tooth depth. Since this restraint moves in sequence toward the dies smaller in tooth depth, the stock retracting in forming the hoop is fed in only the unformed side of the 1st stage of forming where the tooth depth is the smallest. Besides, since the elongation of the stock need not be expected thoroughly, the tooth profile 1a uniform in pitch can be formed continuously and surely all over the peripheral length of the hoop 1.