Тhis work presents data on the functional state and reservatogenic changes of the largest integral massif of the psamophytic steppe which is situated in the island of Khortytsia. The research was conducted by the authors from 1996 till 1997, from 2010 till 2012 and from 2016 till 2018 by means of general geographic, floristic and geobotanical methods of field studies using systematic, biomorphological, environmental coenotic, and geographical analysis. The flora of the territory of 11 hectares includes 136 species of vascular plants from 103 genera of 40 families. The spectrum of 10 leading families in the studied flora coincides with other steppe spectra: such as, Asteraceae, Poaceae, Caryophyllaceae, Scrophulariaceae, Apiaceae, Rosaceae, Fabaceae, Lamiaceae, Brassicaceae, Ranunculaceae. The grassland is dominated by steppe and meadow-steppe species from xeremosophytes and mezoxeremosophytes. Partial domination of species Stipa pennata L., S. capillata L. and Festuca valesiaca Schleich. ex Gaudin characterizes this territory, as steppe groups with a well-preserved kernel of steppe species characteristic of primary groups that have undergone minor anthropogenic influences. Yet the 27 ruderal species segetal group indicates the negative impact of recreation on the territory, as evidenced by the highest percentage of representation for this group of plants ecotonic areas adjacent to public recreation areas that are most exposed to trampling. It was determined that there were phytocenoses degressive reservatogenic changes. It is confirmed by a decrease in the percentage of projective coverage, a decrease in the proportion of species of the genus Stipa L., a change in the floristic composition as to increase the participation of segetal and ruderal and adventitious species. Degradation processes are manifested, first of all, in ecotonous areas with increased recreational anthropogenic pressure. Estimation of functional state and reservatogenic changes of steppe psamophytic groups in Khortytsia island is an urgent and necessary step for determining the tends of changes in valuable zonal phytogroups, the feasibility of developing and implementing scientific substantiation of the relevant regulatory measures.