The aim of the paper: elucidation of some aspects in the ,,parasite-host” system consisting of mermitids (Nematoda, Mermithidae) and heterotopic insects (Díptera, Chironomidae). In order to study the life cycles of the partners of the ,,host-parasite”system, the cultivation of chironomids in laboratory conditions was undertaken. Entomopathogenic nematodes are characterized by a wide range of hosts, high virulence, harmlessness for non-specific organisms, increased efficiency under favorable conditions. These particularities determine their importance as natural biological regulators of some harmful insects.
