MDR-TB is characterized by a low rate of treatment success, including through loss of follow-up. One way to improve treatment outcomes for these patients is to design loss to follow-up prevention interventions based on predictors of this outcome. Aim: to determine the factors associated with the loss to follow-up of patients with multidrug-resistant tuberculosis of Mycobacterium tuberculosis in the Russian Federation. Methods. Multicenter retrospective cohort study. The univariate and multivariate (with the calculation of the adjusted odds ratio - aOR) analysis examined data on 1622 cases of RR / MDR-TB treatment with successful treatment (1338 cases) and loss to follow-up (284 cases). Treatment cases with other outcomes were excluded from the analysis. Differences were considered statistically significant at p f other authors. Conclusion. Loss to follow-up of RR / MDR-TB patients is a self-replicating problem contributing to the spread of drug-resistant Mycobacterium tuberculosis, the solution of which could reduce both the overall burden of tuberculosis and the mortality of patients with tuberculosis. It is necessary to introduce more extensive measures to motivate patients and provide psychosocial assistance to patients with tuberculosis, paying priority attention to the group of male patients with combined pathology of tuberculosis and HIV infection, who previously had default treatment.