Prison inmates have high prevalence rates for both HIV and AIDS, creating a great need for HIV prevention efforts. We tested the theory of planned behavior (TPB) in 3 domains: intention to engage in condom use when released, intention to not share tattoo equipment in prison, and intention to not share needles or tattoo equipment when released. A total of 478 inmates (87% male) completed TPB and sexual and needle-use risk behavior measures. TPB constructs accounted for a significant variance in intention to use condoms among African American, Hispanic, and Caucasian inmates, though the strength of the relationships differed by ethnicity. The TPB was less successful for intention to share tattooing equipment and not to share needles or tattoo equipment after release.