Studies of the taxonomic composition of microalgae of the indigenous channel of the Volga River were carried out in June, August 2024–2025 at 10 stations (district of Dubovka-Bundino village, Kamenny Yar village, Staritsa village, Solenoe Zaimishche village, Tsagan-Aman village, Enotaevka village, Seroglazovka village, Zamyany village, Dawn village, Ikyany village ripple). During the study period, 40 samples were collected and processed. The floristic diversity of phytoplankton over two years was represented by 187 species with a rank below the genus.