Planning of conservation of endangered species populations requires an objective assessment of the species current conservation status. For this purpose, the dynamics of localities was investigated for red-listed vascular plant species in the Leningrad Region. The database of red-listed species records over the period of regional botanical observations (6745 records of 202 species for 200 years) was compiled and served as a base for the trend analysis. This method allowed us to identify four types of the dynamics of localities: positive dynamics (51 species), slightly positive dynamics (56 species), slightly negative dynamics (23 species) and negative dynamics (30 species). The species recorded in a few localities (42 species) were analyzed separately. Ecological-coenotic preferences were defined for the species with different types of the dynamics of localities. The correlation between localities number and the extent of floris-tic observations in the region and human-induced transformation of vegetation are also discussed. As a result, some red-listed species were recommended for clarification of their current conservation status.