A mold material is mounted on a mold material mount portion of a cutting/working apparatus and rotated about the C-axis serving as the rotation center while a cutting tool is driven and moved in directions X and Y. Then, a desired position of the mold material is cut with the cutting tool at a relatively formed desired cutting speed and elliptically vibrated/cut with the cutting tool, for forming a Fresnel lens molding cavity having an opening of a desired shape and a working surface (concave surface, for example) of a desired shape. The productivity of an optical component mold employed as the structure can be efficiently improved when the mold for molding an optical component such as a Fresnel lens is worked by cutting the mold material employed as a workpiece with the cutting tool in a four-spindle lathe-type cutting/working apparatus including X-, Y-, Z- and C-axes of rotation.