The object is to make it possible to pass an electric current to the object of polishing with a stable current density distribution up to the end point of polishing, to use the same plating apparatus, cleaning apparatus and other apparatuses as those conventionally used, and to carry out the conventional manufacturing process flow. A substrate (1) provided with a metallic film (2) and a opposite electrode (3) are disposed oppositely to each other with a predetermined distance therebetween in an electrolytic solution, and an electric current is passed to the metallic film (2) through the electrolytic solution by an anode (4) set out of contact with the metallic film (2), so as to electropolish the metallic film (2). Simultaneously with the electropolishing, wiping is conducted by sliding a pad on the metallic film.