[in Russian with English summary: ] For a comprehensive assessment of the habitats of rare and vulnerable lichen species, 4 key sites in the Eltsovsky, Togulsky and Zarinsky districts of the Altai territory were studied. Plant communities – spruce forests, forests with spruce and cedar pine, as well as fir and aspen forests were described. Seven species of lichens listed in the Red data book of the Altai territory (2016) were found in the studied forests: Graphis scripta, Lobaria pulmonaria, Nephroma bellum, Ramalina roesleri, R. sinensis, R. vogulica, and Usnea longissima. Ecological preferences are indicated for each species, and the population density is calculated. Key words. Biodiversity, biologically valuable forests, lichenized fungus, monitoring the state of populations, population structure, red data book.