PURPOSE: To provide the manufacture of a corrugated metal tube which is free from reduction in strength at the weld part of a metallic tape.

CONSTITUTION: A traveling metallic tape 1 made of steel, stainless steel, etc., is formed in a cylinder by a forming device; the side edges of the metallic tape a are allowed to abut at the seam for welding to form a metallic tube, which is worked for corrugation. When the tailing end part 1a of the metallic tape 1 is joined with the leading end part 1b of a newly supplied metallic tape 1, an inclination is given at the angle of 30-80 degrees to the longitudinal direction so as to cross the corrugating direction of the metallic tape 1, the cut end parts 1a and 1b of both metallic tapes are allowed to abut, welded and joined.