In this study, research was carried out related to the identification of some micromycetes strains as a source of bioactive principles with application in beekeeping. Thus, 22 strains of micromycetes, representatives of the genus Penicillium, were studied according to their antimicrobial properties against Aspergillus niger and Aspergilus flavus, pathogens of aspergillosis, and Paenibacillus larvae, pathogen of the American and European loci. Сatalase activity was also studied. As a result, 5 strains of micromycetes were selected, possessing significant enzymatic and antimicrobial properties that will be further studied to obtain preparations of microbial origin as an alternative to the antibiotics used in beekeeping.