Abstract. Adolescence is a very important period in a person's life. It is at this time that a conscious attitude to health begins to form and a predisposition to chronic diseases is laid. The high workload of schoolchildren and adolescents leads to a sedentary lifestyle, impaired posture, decreased vision, stress and other health problems. Prevention of diseases of adolescents of different ages will allow children not to acquire a whole bunch of diseases. What are the chronic diseases that are common and how to prevent the occurrence of diseases in adolescents, and to know prevention is relevant today.