Abstract: A high-strength, self-supporting thin-film material is provided, which can be widely used and enables accurate structure designing thereof and which can be produced in a simple manner. The thin-film material comprises a polymer thin-film layer that presents a hydroxyl group or a carboxyl group on the surface thereof, and a metal oxide thin-film layer or organic/metal oxide composite thin-film layer that bonds to a polymer thin-film layer in a mode of coordinate bonding or covalent bonding by utilizing the hydroxyl group or the carboxyl group, and has an overall thickness of at most 300 nm.