Approximately 17,150 State and Federal prisoners were living with HIV infection at the end of 2015. The rate of HIV among State and Federal prisoners in 2015 was 1,297 per 100,000 State and Federal prisoners. This was the lowest rate reported during the 25 years in which such data have been reported. In the most recent 5-year period, the number of male prisoners with HIV declined from an estimated 18,510 in 2010 to 15,920 in 2015. During the same period, the number of female prisoners with HIV declined from 1,780 to 1,220. Female prisoners experienced a larger percentage decline. The number of AIDS-related deaths among State prisoners fluctuated from 2010 to 2015 from a low of 45 (preliminary count) in 2015 to a high of 74 in 2012. Over the same period, the annual number of AIDS-related deaths among Federal prisoners has been less than 10, with one death reported in 2015. Between 2010 and 2015, in both number and rate, more male State prisoners than female prisoners and more non-Hispanic Black State prisoners than non-Hispanic White and Hispanic State prisoners died from AIDS-related causes. In 2015, 15 jurisdictions reported mandatory testing of all prisoners for HIV. The website for the full report is included. Whereas this summary contains 1 figure, the full report contains 1 figure and 17 tables.