It is an object of the present invention to provide a material for an antireflective film that has high etching selectivity with respect to the resist, that is, that has a faster etching speed than the resist, a pattern formation method for forming an antireflective film layer on a substrate using this antireflective film material, and a pattern formation method using this antireflective film as a hard mask for substrate processing. The present invention provides a silicone resin for preventing reflection comprising an organic group comprising a carbon-oxygen single bond and/or a carbon-oxygen double bond; a light-absorbing group; and a silicon atom whose terminal end or ends are Si--OH and/or Si--OR. It also provides an antireflective film material comprising this silicone resin (A) for preventing reflection film, an organic solvent (B) and an acid generator (C).