The relevance of the study is due to the insufficient use of the biopotential of the supportive, connective and integumentary tissues of fish (bones, cartilage, fins, heads, scales, skin), which are considered by many scientists as sources of valuable biologically active substances that can be used as functional ingredients in food biotechnology. Collagen and its hydrolysis products, chondroitin sulfate, glycosamine, hyaluronic acid, minerals (calcium, phosphorus, potassium, magnesium, etc.) are the most important components in maintaining human health and, especially, in the prevention and treatment of diseases of the musculoskeletal system. Therefore, the use of hydrolyzed fish tissues as sources of biologically active substances is promising. The biotechnological method of raw material degradation (enzymatic hydrolysis) is the most appropriate, allowing not only to preserve the biopotential of the native tissues, but also to ensure the reliability and sustainability of the production process. The article presents the results of the study of the chemical composition of fish supportive, connective and integumentary tissues, describes the technologies for obtaining new products using these biologically active substances generated by enzymatic hydrolysis.