Introduction. Osteoarthritis of the knee joint is a progressive incurable disease, which in the case of a severe course at a late stage leads to total joint replacement. Recently, experts have focused their attention to the prevention and treatment of early osteoarthritis, so it is important to understand the prevalence, frequency, and modified risk factors for knee OA. The aim is to investigate the patterns of morbidity and prevalence of osteoarthritis of the knee joint on the basis of scientific analysis of relevant modern literature. Materials and methods. Research material – scientific articles in the MEDLINE database for the period 2016–2020, reflecting the epidemiological indicators of osteoarthritis of the knee joint, and additional search for articles from bibliographic lists of selected literature sources. Research methods – a systematic review of relevant sources of literature. Results. Osteoarthritis of the knee joint is one of the most common diseases of the musculoskeletal system. The frequency of osteoarthritis steadily increases with age, overweight. The progressive nature of the disease, the presence of persistent pain lead to limited functionality and reduced efficiency; such patients in some cases require surgical treatment aimed at replacing the compromised joint, which requires significant economic costs, medical rehabilitation and social readaptation of patients and is a heavy burden for both the patient and society as a whole. The lack of correlation between clinical symptoms and radiological signs of osteoarthritis of the knee joint leads to low availability of orthopedic care: more than 30 % of patients with a first diagnosis have a pronounced stage of the disease, and in some cases the pathology is diagnosed only in connection with complications; the diagnosis of osteoarthritis due to the high percentage of painless development of the disease (40 %) is often established in the terminal stages. All this indicates the need for further research on various factors influencing the frequency, prevalence, economic and social burden of osteoarthritis of the knee. Conclusions. Osteoarthritis of the knee joint is characterized by high incidence, which increases with age, progressive course, limited functional capabilities. Treatment of such patients requires significant economic costs of society. A significant increase in the prevalence of osteoarthritis of the knee is associated with increased life expectancy, obesity and some other factors that require further research.