The article discusses the features of microbiocenosis in pesticidecontaminated soils of Karakalpakstan. The results of studies in the region show that soil pollution with pesticides and salinization changes the ratio between individual groups of soil microorganisms and leads to a depletion of the species composition and the dominance of the most adapted to pesticides, salinization of microorganisms. Reduced biodiversity with a predominance of certain groups of soil microorganisms indicates low environmental sustainability.