There is provided a fluorine-containing optical material and a fluorine-containing copolymer which have excellent heat resistance and flexibility in addition to optical characteristics, particularly a material suitable as a clad material for heat resistant plastic optical fiber. The fluorine-containing optical material comprises from 15 to 62% by mole of a structural unit (a) derived from hexafluoroneopentyl methacrylate, from 12 to 70% by mole of a structural unit (b) derived from methyl methacrylate and from 1 to 40% by mole of a structural unit (c) which is derived from a fluorine-containing monomer and is copolymerizable therewith, and is used as various optical materials, and is useful particularly as a clad material for heat resistant optical fiber.