Short description of important scientific result: Studies of 69 strains of micromycetes on the ability to synthesize lectins. Some strains of micromycetes produce both mycelial and extracellular lectins. However, the activity of mycelial lectins is much higher than that of extracellular lectins. A new lectin strain of the genus Rhizoctonia (Basidiomycota division, the family Ceratobasidiaceae, view Rhizoctonia solani), found its physico-chemical and biological properties. It was found that the biosynthesis of lectins by Rhizoctonia solani micromycete increased 2-fold during the cultivation of the producer on potato-glucose with the addition of amino acids asparagine and threonine in a concentration of 100 ?g/ml, during the stationary phase of population growth. The main stages of purification of lectins of micromycetes and sulfate-reducing bacteria were developed.