The effect of temperature on the Monomer Beactivity Eatios(MRR) of copolymerization of acrylonitrile with methyl acrylate in aqueous solution was studied by means of gas chromatography. We obtained r1 = 0.96

r2 = 1.18 at 30℃; r1 = 0.83

r2 = 1.17 at 40℃; r1 = 0.70

r2 = 1.17 at 50℃; r1 = 0.68

r2 = 1.10 at 60℃.The relationship between MRR and temperature is as follows:Inr1 = -4.043 + 1207/T

Inr2 = - 0.01360 + 51.68/T.It has been discovered that the temperature dependence of MRR is considerably affected by the adsorption on the deposit particles of the copolymer for this copolymerization system.