This article describes the characteristics of the beetle fauna – inhabitants of fruiting bodies and the mycelial layer of the true tinder fungus Fomes fomentarius L.: Fr. and are considers some important aspects of the ecology of mycetophilous beetles. Coleopteran population of fruiting bodies of the fungus in five districts of the Saratov region is 63%. Two species from the family Staphylinidae (Gyrophaena joyi Wendeler, 1924 and Scaphisoma boreale Lundblad, 1952) have been recorded on growing and / or spore bearing fruiting bodies.