Ultrafiltration membranes were prepared from a copolymer of acrylonitrile and N-vinylimidazol containing 25.4 mol% N-vinylimidazol. The water permeability and membrane selectivity were measured. The asymmetric structure of the membranes was proved by SEM. The membranes obtained were used as carriers for immobilization of glucose oxidase (GOD). The bound glucose oxidase was found to have high relative activity (91%). The temperature and pH optima, as well as thermal stability of the bound GOD were studied and compared with these for free enzyme. The kinetic parameters of the enzyme reaction - Michaelis constant (k(m)) and maximum reaction rate (V-max) were investigated. The results obtained show that ultrafiltration membranes prepared from copolymer of acrylonitrile and N-vinylimidazol are suitable for use as carriers for immobilization of glucose oxidase.