To provide a method of manufacturing a product of a band metal plate and the working machine of the band metal plate by which the variation in the shape of the product of the band metal plats can be suppressed.

According to this working machine 10 of the band metal plate and the method of manufacturing the product of the band metal plate 10 using the working machine of the band metal plate, because a lapped folding part 91 is formed by pressing the preliminarily bent part 92 with a pair of press tools 38, 38 after forming preliminarily bent part 92 beforehand in the half-way part of the band metal plate 90, the shape of the lapped folded part 91 is constant and the variation in the shape of the product W of the band metal plate is suppressed.