There is disclosed a bottom resist layer composition for a multilayer-resist film used in lithography which comprises, at least, a polymer having a repeating unit represented by the following general formula (1). Thereby, there can be provided a bottom resist layer composition which shows an antireflection effect against an exposure light by combining with an intermediate resist layer having an antireflection effect if necessary, has a higher etching resistance during etching a substrate than polyhydroxy styrene, cresol novolac resin, etc., has a high poisoning-resistant effect, and is suitable for using in a multilayer-resist process like a bilayer resist process or a trilayer resist process.