This review presents the literature data on classification of non-tuberculosis mycobacteria, prevalence, epidemiology, clinical picture. The analysis of the research results reveals the prevalence of mycobacteriosis in the world, the main ways of transmission. Some data of clinical recommendations of the British thoracic society (BTS) 2017 on the algorithm of examination and diagnosis of mycobacteriosis are presented. Treatment of mycobacteriosis is a difficult task, the effectiveness of therapy remains extremely low. According to the British researchers, the proportion of patients with mycobacteriosis caused by MAC, M. malmoense , M. xenopi , who received various regimens of therapy and completely completed the course of treatment with positive clinical and laboratory dynamics, as well as did not have relapses within a year after treatment, is only 28%. According to other studies involving patients with specific types of NTMB, the effectiveness of therapy ranges from 30-50% for diseases caused by M. abscessus , 50-70% for MAS and about 80-90% for M. malmoense and M. Kansasii .