PROBLEM TO BE SOLVED: To provide a decoration method to obtain a decorated molding provided with a metallic surface appearance by laminating a thin metallic film on a surface of a synthetic resin molding, which can provide delicate patterns on a metallic appearance, provide a three-dimensional visual effect as if convexoconcave patterns were formed by etching the metal, and enables patterns to be easily changed according to the purpose of decoration.SOLUTION: The decoration method comprises: forming a printed layer on a predetermined area of a surface of a synthetic resin molding by an inkjet printer with on-demand functions and roughening the predetermined area of the surface with this printed layer; and coating the surface of the molding with a metal thin film layer with the printed layer interposed, and providing the metal thin film layer with a crepe-like surface appearance by means of the roughened printed layer.
