To provide an organic-inorganic composite film having high strength and flexibility, to provide a method for producing the organic-inorganic composite film, and to provide an antireflection film and an insulation film which use the organic-inorganic composite film.

In the method for producing an organic-inorganic composite film by a plasma CVD process under the atmospheric pressure or under the pressure in the vicinity thereof, a metal element-containing compound and an organic compound are decomposed and excited under different plasma conditions, and then are mixed on a base material, thereby performing a film deposition.