Species distribution and composition of the genus Usnea in Buryatia Republic (Russia) are discussed. Records of 11 Usnea species were cited for Buryatia in literature, 10 of them have been confirmed by examination of herbarium materials. Morphological changes of thallus growth pattern (shortening of main branches and increasing number of fibrils and lateral branches resulting in formation of brush-like thalli) in extracontinental environment are described. Keywords: Usnea, Republic of Buryatia, Russia.