The tuberculosis incidence rate in prisons in Rio de Janeiro State, Brazil, was 30 times higher in 2004 than in the general population and is probably underestimated, particularly given the difficult access to care in the prison setting. To obtain a better estimate, a survey used systematic X-ray screening and showed a prevalence rate of 4.6% in one such detention facility, A (n = 1,052). Two additional surveys, in facilities B (n = 590) and C (n = 1,372), showed even higher prevalence rates (6.3% and 8.6% respectively). A comparison of socio-demographic characteristics between A, B, and C showed a heterogeneous prison population. As compared to facility A, inmates in B and C come from poorer urban communities and have more frequent histories of incarceration and tuberculosis. These differences, consistent with the prevalence data, imply the necessary adaptation of tuberculosis control programs to each detention facility's epidemiological and socio-demographic profile.