The polymerization of methylmethacrylate and acrylonitrile initiated by copper(II) complexes was studied in the presence of carbon tetrachloride. The polyvinylamine derivative(I) and (II) which have about 45 and 62 percent degree of the N-methylation were used as ligands and also polyvinylamine itself was used for comparison. The activity of the substituted amino complexes for the polymerizations of the monomers was found to be higher than that of the amine complex. The apparent activation energy of the polymerization of methylmethacrylate initiated by the substituted amine complexes was higher than that of the polymerization of methylmethacrylate initiated by the amine complex. These results can be attributed to the difference in instability between the complexes formed with different amines due to the steric hindrance extended by methyl group. The activity of the methylated amino(II) complex for the polymerization of methylmethacrylate was rather lower than that of the methylated amine(I) complex. This result may be due to the presence of hydrogen of amino groups.