This invention provides a manufacturing method of printed wiring board which enables a plate-like substrate to be carried and processed without any contact to its product surface. End portions of plate-like copper clad laminates are overlapped vertically and then joined linearly by rotating an ultrasonic horn along the end portions. Consequently, copper foils can be metal-joined and a joining strength necessary for transportation with a roller is obtained. Because belt-like copper clad laminate is obtained by joining the plate-like copper clad laminates and after that, processed, thus, the belt-like copper clad laminate can be carried without any contact to its product surface as it is carried with the roller, and then processed.