Sputtering method and apparatus for forming a coating on both sides of a flat substrate or on the entire surface of a bulky substrate without involving rotation of the substrate. At least one pair of sputtering cathodes each having a target attached thereto are arranged in a film-forming chamber capable of controlling a vacuum atmosphere with their target sides facing each other, and a substrate is disposed in front of the targets. A voltage is applied to the sputtering cathodes in such a manner that the polarity alternates between the sputtering cathodes making the pair to induce a glow discharge between the sputtering cathodes. The target on each sputtering cathode is thereby sputtered and deposited on the substrate.