To provide efficient and economical manufacture of flat foil corrugated with micro-waves (ripples) being an useful structural member of metal honeycomb-body to carry catalyst for purification of exhaust gas.

In the manufacture of the flat foil corrugated with the micro- waves (ripples) as the structural member of metal honeycomb body to carry the catalyst for purification of exhaust gas, when a long length flat foil is sent toward lengthwise direction and passes through a pair of upper and lower corrugation forming roll, a flat foil is passed through at least two or more corrugated stations (S=S1+S2+......Sn; n is 2 or more integer) forming corrugations toward width direction (perpendicular direction to the lengthwise direction of the long-length flat foil), and two or more corrugated stations (S=S1+S2+......Sn; n is 2 or more integer) as well so that tooth profile configuration of corrugation forming roll at each corrugated station may be constituted so as to change pitch width successively from large ones to small ones, and the micro-waves (ripples) are made form toward width direction.