The copolymer of tributytin methacrylate and methylmethacrylate is a useful self-polishing antifouling paints materials. It was synthesized by radiation polymerization using ,60,Co ,γ, ray at room temperature. It was carried out to study the copolymerization kinetics of the pair of monomers. The relationship between the reaction rate and the dose rate was found to be R,P,=K,P,•I,0.53, and the reactivity ratios were measured to be lass than 1. The overall activition energy was 1.29×10,4,J/mol. It was Supposed that the copolymerization was of radical machanism.