Abstract: The aim of research was to evaluate the influence of white light on the growth,sporulation and pathogenicity of entomopathogenic fungi Isaria fumosorosea and Beauveriabassiana. The study indicated that white light was an important factor, affecting the sporulationof entomopathogenic fungi. Fungi grown in total darkness sporulated very faintly. However thefungi which were irradiated during the period of growth, showed considerably better ability toproduce spores. The highest production of spores was achieved when fungi were grown in totaldarkness for the first three days, and next under exposure to white light. The exposure ofmycelium to white light did not influence the germination ability and pathogenicity of harvestedspores against test insects.