Incarcerated populations have relatively high HIV prevalence but little has been reported about their aggregate HIV risk behaviors or perceptions of risk. A random selection of HIV-negative men (n = 855) entering a US state prison system were surveyed to assess ﬁve risk behaviors and his self-perceived HIV risk. Using multivariate logistic regression, we identiﬁed factors associated with having elevated actual but low perceived risk (EALPR). Of the 826 men with complete data, 88% were at elevated risk. While 64% of the sample had risk perceptions concordant with their actual risk, 14% had EALPR (with the remainder at low actual but high perceived risk). EALPR rates were lower in those with a pre-incarceration HIV test but higher for those with a negative prison entry HIV test. HIV testing counseling should assess for discordance between actual and perceived risk and communicate the continued risk of HIV despite a negative result.