The method of identifying potential areas of protected plant species with the use of geoinformation analyses is discussed in the example of one mountain territory (Tanzybei management polygon, 168 000 ha) within the Altai-Sayan ecoregion. Four altitudinal belt complexes (ABC) form the spectrum of barrier-rain mountain landscapes on the windward macroslope of Western Sayan — from mixed pine-birch forest with Pinus sylvestris and Betula pendula (light-coniferous subtaiga, 300–500 m) and chern mixed forest with Abies sibirica, Pinus sibirica and Populus tremula (350–900 m) to middle-mountain perhumid taiga with Abies sibirica (900–1350 m) and subalpine sparse woodlands with Pinus sibirica and Abies sibirica (1350–1600 m). The current importance of this research is dictated by a particular significance of a specific class of barrier-rain specific ecosystems for a classification of mountain landscapes of Siberia. Field route and station-based investigations made during 1960–2015, and also materials on forest inventory were systematized in the form of regional databases on the typological composition of forests, vegetation and flora and combined with the regional geoinformation system of the Tanzybei district forestry. This provided the initial ecological-geographical basis for subsequent efforts on the compilation of analytic maps. Results were tested and verified during subsequent field route investigations. Examples of analytic maps are given. The method developed for identifying potential areas of species by using the authors’ databases on flora and vegetation, ecological-geographical approach and geoinformation analyses serves to obtain new knowledge of geographical content.Keywords: protected plant species of barrier-rain landscapes, altitudinal belt complex (ABC), Pinus sibirica-Abies sibirica chern forests, series of forest types, forest inventory, GIS, analytic maps.