The article presents results of research of feeding of humpback whitefish in the conditions of high‑mountainous lake Sorulukol (Altai Republic). Prevalence of gammarids and mollusks in humpback whitefish’s diet is noted. Humpback whitefish mainly eats mollusks of families Sphaeriidae and Euglesidae. Gastropod mollusks (Lymnaeidae) also meet in food lumps, but in smaller quantity.