Long-term dynamics of growth areas and biomass of macrophytes of the phytocenosis Chara aculeolata Kütz. in the Tendrovsky Bay of the Black Sea was analyzed. Partial degradation of the phytocenosis has been observed since 1993. In the period 1993 - 2010, the area of the phytocenosis decreased from 100 km2 to 6.3 km2. After partial degradation in the period 2010 - 2021, elements of regenerative succession were observed. Monitoring of the Chara aculeolata Kütz. phytocenosis recovery in Tendrovsky Bay showed a gradual slow expansion of growing areas and growth of productivity over 10 years of observation and sudden boom in 2021. Currently the C. aculeolata phytocenosis is spread over an area of 36 km2, and the maximum biomass of the dominant species reaches 1800 г·м-2. The possible reasons of the observed changes are discussed.