To provide a fluorinated elastic copolymer having a low content of metal elements and being excellent in crosslinkability. This fluorinated elastic copolymer has iodine atoms and has units a based on tetrafluoroethylene, units b based on a monomer having one polymerizable unsaturated bond (but excluding tetrafluoroethylene), and units c based on a fluorinated monomer having at least two polymerizable unsaturated bonds, wherein the metal content is at least 0.3 ppm by mass and at most 20.0 ppm by mass.