The effect of cadmium, copper, lead, zinc, manganese and magnesium on entomopathogenic nematodes S. feltiae was tested under laboratory conditions. The mortality of nematode invasive larvae, their pathogenicity expressed as test insect G. mellonella mortality and reproduction from the test insect bodies were investigated. It was revealed that cadmium, copper, lead and zinc affected an increase of S. feltiae nematode invasive larvae mortality, decreased their pathogenicity for test insects and reproduction. Manganese in 400 mg·dm-3 Mn (II) concentration positively affected entomopahogenic nematode S.feltiae during their storage causing decreased mortality, improved pathogenicity and reproduction from insect bodies in comparison to distilled water.