Abstract: For improving both coplanarity and bending accuracy of gull wing type outer leads of electronic parts such as resin molded semiconductor devices, quad flat packages, etc., a lead forming machine is used which incudes a bending die and a stripper which have a pair of faced projections at both sides thereof, and bending punches vertically moving through perforations of the stripper. An electronic part with gull wing type outer leads is disposed between the bending die and the stripper in such a manner that the outer leads extend horizontally from the projections of the bending die. In this case, both sides of outer leads are placed on projections of the bending die without clamping them with the faced projections of the bending die and the stripper. The bending punches are depressed through perforations of the stripper to perform primary lead forming for the outer leads.