This article studies the indicator properties of gastropods common in the Upper Syr Darya River basin. They are divided into ecological groups according to their habitats. The generally accepted ecological and zoological methods were used in the research. According to the research results, fresh-water gastropods of the Fergana Valley inhabit xenosaprobic, oligosaprobic, β – mesosaprobic, α – mesosaprobic and β – polysaprobic waters. Molluscs are mainly distributed in stagnant water bodies. The substrate of most mollusks are aquatic plants