The Brechovo mire is a natural monument of the Ulyanovsk region, it is a stratigraphic standard of the Holocene period, the place where rare and medicinal plant species grow and has significant reserves of a valuable natural resource – peat. Currently, it is exposed to a number of anthropogenic factors, which causes concern for the safety of its natural complexes. The article is based on the description of trial plots (total 96 descriptions). Field geobotanical studies (area descriptions and geobotanical mapping) were carried out according to generally accepted methods.