The copolymerization of MTMP(2，2，6，6-tetramethyl-4-piperidinylmethacrylate，M1) with St(styrene，M2)，MVK(Methylvinylketone，M2)，AN(acrylonitrile，2)and VAe (vinyl acetate，M2) was conducted in benzene at 60±0.1℃ by using ABVN (or AIBN) as initiator．The composition curves of the eopolymers and the monomer reac-tivity ratios of four pairs of monomers have been determined(MTMP．St：γ1=0.30士0.05，γ2=0.63±0.05；MTMP-MVK；γ1=0.53土0.05，γ2＝0.41±0.05；MTMP．VAc：γ1=14土0.5，γ2=0.02±0.01；MTMP—AN：γ1=13.7±0.5，γ2=0.20士0.05)．The Q(0.56) and e(0.49)values of MTMP have been calculated and the microstructure of the copolymer has been described．