To provide a fluoropolymer having functional groups and having high transparency in a wide wavelength region, and a resist composition comprising the fluoropolymer. A fluorinated copolymer having units derived from a monomer unit formed by cyclopolymerization of a fluorinated diene represented by the following formula (1): CF.sub.2.dbd.CFCH.sub.2CH(CH.sub.2C(CF.sub.3).sub.2(OR.sup.1))CH.sub.2CH.- dbd.CH.sub.2 (1) wherein R.sup.1 is a hydrogen atom, an alkyl group having at most 20 carbon atoms, which may have an etheric oxygen atom, an alkoxycarbonyl group having at most 6 carbon atoms, or CH.sub.2R.sup.2 (wherein R.sup.2 is an alkoxycarbonyl group having at most 6 carbon atoms), and units derived from a monomer unit formed by cyclopolymerization of another monomer or units derived from a monomer unit formed by polymerization of an acrylic monomer, and a resist composition having such a fluorinated copolymer as a base polymer.