A chemical amplification type positive resist composition, which can reduce cost steeply without significantly decreasing basic abilities, is provided, and the chemical amplification type positive resist composition includes (A) a resin having a polymerization unit derived from p-hydroxystyrene and a polymerization unit of the formula (1) or formula (2) ##STR00001## which is insoluble or poorly soluble itself in an alkali aqueous solution but becomes soluble in an alkali aqueous solution by the action of an acid, (B) a resin obtained by protecting a portion of the hydroxyl groups in poly(p-hydroxystyrene) with a protective group not dissociating by the action of an acid or a resin obtained by substituting a portion of the hydroxyl groups in poly(p-hydroxystyrene) with hydrogen, and (C) an acid generating agent.