Insecticidal soil fungi are used for the biological control of pests of cultivated plants. Fungi of the Fusarium genus are economically important phytopathogens that produce mycotoxins. The aim of the study was to identify the effect of selected insecticidal fungi on the growth and development of Fusarium fungi. Study material were the strains: F. culmorum, F. avenaceum, F. poae, Beauveria bassiana, Isaria fumosorosea and Metarhizium anisopliae. Identification of interactions between strains was conducted in laboratory conditions using three media: Potato Dextrose Agar, Sabouraud Agar, Czapek-Dox. The cultures were incubated and surface growth of colonies was observed. After culturing, interactions between species were assessed using the individual biotic effect score by Mańka. Fusarium fungi prevailed over entomopathogenic fungi in plate cultures. In most cases, Fusarium fungi obtained a positive and relatively high score when cultured in the presence of entomopathogenic fungi. It was demonstrated that entomopathogenic fungi have a poor antagonistic potential against Fusarium fungi. The entomopathogenic species I. fumosorosea, in some cases limiting the growth of phytopathogens, constituted the exception.