To provide a method for enhancing adhesion of a thin film, and a method for enhancing adhesion of a thin film provided with a surface function caused by the shape. Adhesion of a thin film can be enhanced by irradiating the surface of a parent material with a laser beam at a fluence in the vicinity of the machining threshold, scanning the irradiated part while overlapping to form a grating structure, and then forming a solid thin film in the grating structure. When the grating structure formed on the parent material is left on the solid thin film, adhesion of the thin film is enhanced and surface functions, e.g. reduction of friction and wear caused by the shape, suppression of adhesion of fine particles, and cell sensibility, can be exhibited in conjunction with the function of the solid thin film.