PURPOSE: To improve the productivity by dividing forming processes into straight part and curving part in the formation of a metal long body to be meanderously bent.

CONSTITUTION: In the formation of the long body to be meanderously bent composed of (1-C)-(7-C) curving parts and (1-S)-(7-S) straight parts, at a first process, spirally bent long body having the same direction to all bent parts is formed. At a second process, the prescribed curving part is rotated at the prescribed direction and angle and one side of the two straight parts of the extended parts thereof is twisted and the other part thereof is displaced and group of the straight parts is arranged on the prescribed same plane. By this method, the productivity of the forming work is improved and also possibility of mechanization to this work is given.