The present invention provides a resist composition giving a resist pattern excellent in CD uniformity and focus margin. A chemically amplified photoresist composition comprises a resin (A) and an acid generator (B), and the resin (A) contains, as a part or an entirety thereof, a copolymer (A1) which is obtained by polymerizing at least: a (meth)acrylic monomer (a1) having C5-20 alicyclic hydrocarbon group which becomes soluble in an aqueous alkali solution by the action of an acid; a (meth)acrylic monomer (a2) having a hydroxy group-containing adamantyl group; and a (meth)acrylic monomer (a3) having a lactone ring, and the copolymer (A1) has a weight-average molecular weight of 2500 or more and 5000 or less, and a content of the copolymer (A1) is not less than 50 parts by mass with respect to 100 parts by mass of the resin (A).