Bioactive feed additives inhibiting growth of pathogenic and opportunistic microorganisms, proliferating development of intestinal bifido- and lactobacteria, stimulating gut peristalsis, promoting assimilation of macro- and microelements, activating specific and non-specific protective systems, displaying absorbing and other beneficial properties, have been actively introduced into farm stock rations in recent years. Research and development is under way to produce new feed supplements based on live yeast cultures or combinations thereof with pro/prebiotics, enzymes, and other bioactive substances. The investigations are going on to evaluate functional performance of yeast components of feed formulas, including enzymatic, antagonistic, probiotic activities and the role in rumen microbial cenosis [1-4]. The aim of this study – screening of 40 collection cultures of yeast-like fungi from genera Rhodotorula, Saccharomyces, Torulaspora, Rodosporidium, for the ability to produce enzymes involved in plant polysaccharide and lipid biodegradation. According to the obtained data, all examined yeast strains synthesized lipase. Pectolytic activity was found in 85% of tested variants – in all representatives of Rhodotorula genus, in 17 (74 %) out of 23 Saccharomycetes, and in Torulaspora delbrueckii BIM Y-38 and Rodosporidium kratochvilovae BIM Y-157 strains. Protease production was detected in 23 strains (57 %), alginase and beta-glucanase synthesis – in 6 (15 %) and 7 (17.5 %) yeast cultures, respectively, while beta-galactosidase activity was revealed only in Saccharomyces cerevisiae BIM Y-125 strain. With respect to specific enzyme synthesis, the highest activity was shown by Saccharomyces cerevisiae BIM Y-125 (amylase), Rhodotorula glutinis BIM Y-159 (protease, pectinase, alginase), R. glutinis BIM Y-33 (protease, lipase), R. glutinis BIM Y-138, R. lactosa BIM Y-118 and R. mucilaginosa BIM Y-162 (lipase), R. lactosa BIM Y-113 (beta-glucanase). The most plentiful spectrum of generated enzyme complex comprising 5 constituents was recorded for strains Rhodotorula glutinis BIM Y-159 (protease, pectinase, lipase, alginase, and beta-glucanase) and Saccharomyces cerevisiae BIM Y-125 (amylase, protease, pectinase, lipase, beta-galactosidase). Strain Rhodotorula minuta BIM Y-113 was distinguished by biogenesis of 4 enzymes (protease, pectinase, lipase, and beta-glucanase). The remaining strains were able to produce 1 to 3 of 8 enzymes. Strains Saccharomyces cerevisiae BIM Y-125 and Rhodotorula glutinis BIM Y-159 were chosen for further studies aimed at elaboration of biotechnology for production of a complex bioactive feed additive.