The present invention provides a resin comprising a structural unit derived from a compound represented by the formula (I): wherein R1 represents a hydrogen atom or a methyl group, A2 represents a divalent fluorine-containing C1-C12 hydrocarbon group, and A1 represents a group represented by the formula (a-g1): A10-X10sA11-  (a-g1) wherein A10 is independently in each occurrence a C1-C5 aliphatic hydrocarbon group, A11 represents a C1-C5 aliphatic hydrocarbon group, X10 is independently in each occurrence —O—, —CO—, —CO—O— or —O—CO—, and s represents an integer of 0 to 2, and a photoresist composition comprising the resin and an acid generator.