Microscopic fungi are producers of toxic secondary metabolites - mycotoxins. These hazardous substances are often found in animal feed and lead to its increased toxicity. Many strategies have been proposed to eliminate the negative effect of mycotoxins on human and animal health, one of the most promising, but at the same time poorly developed, is the use of antagonists of mycotoxin producers. The aim of the research was to find antagonists of mycotoxin producers. Materials and methods. Soil samples from various regions of the Republic of Tatarstan served as the material for the study, from which isolates of various genera of microscopic fungi (genera Candida, Aspergillus, Penicillium, Tricdhoderma, Fusarium) were isolated. The antagonistic interaction between microorganisms was determined by the method of streak inoculation, "plate" method. Toxigenic strains of F. graminearum, A. flavus, F. sporotrichioides were used as test strains. Research results, discussion. Pure cultures of micromycete isolates were isolated and obtained. Their main cultural and morphological properties were determined, due to which their preliminary identification was carried out to the generic and partly species affiliation. The toxigenicity of the micromycetes themselves was preliminarily assessed and the experiments were carried out only with atoxigenic isolates. Each isolate was assigned a code. Antagonistic relationships have been established between some micromycetes. Fungi of the genus Aspergillus and Trichoderma exhibited antagonism against toxigenic micromycetes F. graminearum and F. sporotrichioides. Yeast fungi, identified by us as representatives of the genus Candida, did not suppress the growth of toxigenic fungi. An isolate antagonist of Trichoderma Tr2 and A. flavus As03 was selected for further research.