The 2,2'-azodiisobutyronitrile-induced radical polymerization in solution of 4-nitrophenyl acrylate was performed under microwave heating at a frequency of 2.45 GHz. This approach allows the control of the molecular mass of poly(4-nitrophenyl acrylate) used in the synthesis of multivalent glycoconjugates. It was found that the polymerization of 4-nitrophenyl acrylate under microwave irradiation results in products with a narrower molecular mass distribution than at conventional heating.