The features of interrelations of Pterostichus melanarius (Illiger, 1798) with the soil and litter mesofauna species are considered. In the conditions of forest ecosystems of steppe Dnieper region P. melanarius demonstrates trophic preference for І order zoofagoes (body mass 8.0–31.9 mg) and also sapro- and phytofagoes (more than 128 mg of body mass). P. melanarius is able to change the trophic load between invertebrates’ populations depending on their number in the ecosystem. In comparison with the other ground beetle species, the P. melanarius has an extraordinarily wide trophic niche. That is one of principal reasons of the high quantity of P. melanarius in many anthropogenic and transformed ecosystems.