To study the optimal conditions for roller cultivation of cold-adapted reassortant vaccine strain of influenza virus A/17/Duck/ Potsdam/86/92 (H5N2) in MDCK and Vero cell cultures grown on nutrient medium based on soy and rice flour hydrolysates obtained using trypsin and bromeline. Vaccine strain was cultivated on MDCK and Vero cells in rollers in the presence of plant proteases. Obtained culture samples of vaccine strains were lyophilized and their infectivity was assessed. Cultivation of vaccine strain on MDCK and Vero cells grown in experimental media containing reduced quantity (2 and 3% respectively) of fetal calf serum ("Gibco", USA) resulted in high titers of the virus in the presence of plant proteases (4 mcg/ml of papain and 20 mcg/ml bromeline). Use of plant enzymes and nutrient media based on enzymic plant hydrolysates, including those obtained with bromeline, for cultivation of vaccine strain on MDCK and Vero cell cultures in rollers could make the manufacturing process of live influenza vaccines safer and more cost effective.