It has been established that the rare arctic-alpine species Rhodiola rosea L. constitutes a vulnerable component of the flora of the Ukrainian Carpathians in modern conditions of the high-mountain areas. Under the influence of climate factors changes are taking place in important components of the species populations to ensure its ability to recover and survive. Hence, the field of research covers the study of the modern state of populations Rhodiola rosea and changes in the basic parameters of structure organization, which determine the prospects for their development and adaptation. Input characteristics of the population status diagnostics is analysis of perennial data on the number of species individuals, reproductive ability and the nature of manifestation of dynamics trends due to the influence of environmental factors. Taking into account the ecological and biological features of the species and, in particular, the attraction to wet and cool habitats with low temperatures, the ambiguous response of populations to changes in climatic conditions is followed. It was found that populations of the species are sensitive to stress situations which lead to considerable violations in the structural organization and, in particular, in changes in demographic, sexual, spatial and reproductive indicators. Of importance for assessing the status of the species populations and for indicating the environmental conditions must be availability of generative individuals and their functional relations with the environment. Population degrading is manifested through reduced number of individuals, disruption of the correlation between different-sex, weakening of reproductive development functions, fragmentation and spatial disintegration of individuals with low renewal activity. Hence, Rhodiola rosea populations are sensitive to environmental changes, in particular, warming, which fact testifies to non-correspondence of current climatic conditions to the ecological needs of the species. At the same time, negative trends are also strengthened by the mechanical destruction of the natural habitats of populations, which significantly slows down the processes of their regeneration ability. Therefore, changes occurring in populations Rhodiola rosea actively affect their structural organization and ability to recover. Based on the application of complex ecological-demographic and reproductive approaches, a number of indicators of the structural organization of populations, their changes during different periods of vegetation and the ability to recover in changed environmental conditions were obtained. The obtained results are important in solving issues related to the preservation of populations of arcto-alpine species, assessment of their development and behavior in modern high-mountain conditions.