The agricultural world is overloaded with chemical substances. Undesirable effects and the resistance of pests open a new way for biological control of pathogenic species of insects. Bark beetles (Curculionidae, Scolytinae) are important pests on conifers such as pines, spruces or firs. As natural inhabitants of coniferous forests, they are also invasive and destructive element after wind storm or during abrupt temperature changes, when plenty of broken or weaken trees become source for their feeding and reproduction. The most common natural pathogens of spruce bark beetle, Ips typographus L., are entomopathogenic fungi belonging to the order Hypocreales. Beauveria bassiana (Bals.-Criv.), a fungus naturally found in soils, is the most important insect pathogen with a wide host range. We hypothesized that the fungus may be a suitable candidate for biological pest control. The aim of this research is to study the prevalence and diversity of these entomopathogenic fungi and their infestation on spruce bark beetles. Dead-infected spruce bark beetles are collected from under a spruce bark and pheromone traps. Collections are carried out at the national park High Tatras in Slovakia (N49°10′ E20°08′). Strains of entomopathogenic fungi are growing on Sabouraund dextrose agar (SDA) at 30°C for 2 weeks. For identification and differentiation of fungus species we use method of isolation the genomic DNA, which analyze for specific DNA segments amplified by PCR method. Study of influence of selected isolates demonstrated positive results for the use of biological protection of forest trees instead of insecticides.