BACKGROUND: TB notifications in Latin American prisons have more than doubled over the past two decades; however, treatment outcomes and their determinants among incarcerated individuals in this region are not well understood.METHODS: Newly diagnosed drug-susceptible TB cases reported to Brazil´s Information System for Notifiable Diseases (Sistema de Informação de Agravos de Notificação, SINAN) between January 2015 and December 2017 were included. Multivariate logistic regression was used to assess socio-economic and clinical factors associated with treatment success among incarcerated individuals.RESULTS: Incarcerated individuals (n = 17,776) had greater treatment success than non-incarcerated individuals (n = 160,728; 82.2% vs. 75.1%; P < 0.0001), including after adjusting for demographic and clinical risk factors (adjusted odds ratio aOR 1.27, 95% CI 1.19-1.34). These differences were partially mediated by increased use of directly observed therapy among incarcerated individuals (DOT) (61% vs. 47%; P < 0.001), which was associated with greater efficacy in the incarcerated population (aOR 2.56 vs. aOR 2.17; P < 0.001). DOT was associated with improved treatment success among incarcerated subpopulations at elevated risk of poor outcomes.CONCLUSION: TB treatment success among incarcerated individuals in Brazil is higher than non-incarcerated individuals, but both fall below WHO targets. Expanding the use of DOT and services for socially and medically vulnerable individuals may improve outcomes in carceral settings.