PURPOSE: To reduce the man-hour and to improve the efficiency of the laminating work by laminating predetermined shape of thin plates while a resist film remains after punching it by etching.

CONSTITUTION: A resist film is formed on the surface of a thin plate of a predetermined soft magnetic material magnetically annealed in hydrogen. Then, after the resist film is patterned, the film is punched by etching. Thereafter, the predetermined shape of thin films are laminated while the film remains. Thus, the insulation between the layers of the laminate can be performed without insulating step, a burr or a shape deformation is eliminated, and the efficiency of the laminating work is raised. In this manner, the man-hour is reduced, and the efficiency of the laminating work is improved.