Abstract: In Slovenia, we started our first studies on entomopathogenic nematodes (EPNs) in2004. Because EPNs had exotic organism status until 2008, all studies undertaken before 2008were limited to laboratory experiments. The aim of our investigations was to examine the controlactivity of different species of EPNs at different temperatures and different concentrations ofsuspension for species of vegetable pest insect (Eurydema ventrale, Phyllotreta spp.). Between2006 and 2009 we were actively involved in studying EPNs presence and abundance inSlovenian soils and from a total of 520 analysed samples we confirmed EPNs in 24 samples. Atpresent we have evidence of the presence of 5 species of EPNs; Steinernema affine (Bovien),S. feltiae (Filipjev), S. carpocapsae (Weiser), S. kraussei (Steiner) and Heterorhabditis bacteriophora(Poinar). The list of indigenous species of organisms used for biological control at presentincludes the last four species of EPNs. For commercial purposes 7 products can now be used inSlovenia. Their active ingredients are EPNs, but none of them is registered at the moment forcontrolling pest insects on vegetables grown outdoors.