When processing citrus fruits into concentrated juice, enterprises generate waste in the form of peel, pit, and pulp. These wastes, especially the peel, are rich in useful biologically active substances. The most representative in terms of content and valuable from the point of view of use in medicine and the food industry, groups of biologically active substances of citrus fruits are flavonoids and carbohydrates. Flavanones are known for their multifunctional and antioxidant action. The dominant flavanone of citrus fruits, hesperidin, can be used as an active substance for the preparation in medicine and in medicinal food products. Research in the ways of using various valuable products from citrus fruit processing waste are presented in foreign scientific sources, while Russian scientists have paid insufficient attention to this urgent problem. This article substantiates and experimentally confirms the optimal method for obtaining hesperidin from citrus fruit processing waste.