A surface treatment method includes covering a surface of a casting mold with a carbon film containing at least one type of nanocarbon selected from the group including carbon nanocoils, carbon nanotubes and carbon nanofilaments, and further applying fullerenes to that surface. With this surface treatment method being performed on a surface (a cavity surface, etc. of a casting mold) making contact with a molten casting material such as aluminum, etc., sticking of the molten casting material to the mold is inhibited, release resistance of the product is reduced, and release effectiveness is improved. The release effectiveness lasts longer than in the case of a conventional carbon film.