Provided is the preparation of a coil-comb block copolymer and a method for producing nanostructures formed by the copolymer. Particularly, provided is a method for producing nanostructured polymer thin films, including: preparing a coil-comb block copolymer via a controlled polymer polymerization process; forming a thin film of the block copolymer on a substrate and carrying out heat treatment to form nanostructures including vertically aligned cylindrical microstructures; and irradiating ultraviolet rays to the thin film and carrying out oxygen plasma treatment to form nanostructured polymer thin films including cylindrical pores.