The Tyumen Region, being the largest one in the Ural Federal District in terms of territory, has a high level of HIV prevalence, particularly among those taken into custody. This group of people involves the maximum number of injecting drug users, men having sexual encounters with other men and sex workers. All acquired diseases including the diseases aggravated during the service of sentence become the problem of the expirees as well as the entire civil society. From an epidemiological perspective it is important to search for the risk factors which are active among the prisoner population serving their sentence in the region and which cause HIV progression with fatal outcome, taking into account their unequal significance among the prisoner population and the civilians.Object of research. 365 HIV-infected, deaths were identified, including: the study group — 222 prisoners, HlV-infected and died at the regional hospital of the Federal penitentiary service of Tyumen for the period 2008-2018; the control group - 143 civil (law-abiding) patients, HIV-infected and died at the Regional infectious diseases hospital for the period 2011-2018.Purpose of research. Identification and assessment of priority risk factors for the expansion of the epidemic process of HIV infection with a fatal outcome in the zone of high concentration of the risk group.Methods of research. The following methods have been used in this work: methods of epidemiological research, methods of mathematical modeling and forecasting, as well as the method, of logistic regression, of step-by-step inclusion with ROC analysis.Results. To assess the epidemiological situation in terms of the HIV infection prevalence in the prison area a long-term and intra-annual dynamics of the epidemic process expansion in the region have been studied along with assessment of the priority risk factors, trends, forecasting of the HIV infection expansion in the penitentiary system specifying the social significance and risks to the civilian population over a long period.