CONTEXT: The relationship between individuals’ perception of their risk for acquiring HIV and their use of condoms is poorly understood. Understanding this relationship is crucial to the development of effective strategies to ?ght HIV and AIDS. METHODS: Data from the Mozambique 2001 Adolescent and Young Adult Reproductive Health and Behavior Risk Survey are used to compare 15–24-year-olds’ assessments of their HIV risk with assessments based on current and past sexual behavior. In bivariate and probit regression analyses, the relationship between correct risk assessment and the likelihood of condom use at last intercourse is examined. RESULTS: Twenty-seven percent of women and 80% of men who considered themselves to have no risk or a small risk of contracting HIV were actually at moderate or high risk. For both men and women, the prevalence of condom use at last sex was more than twice as high among those who assessed their risk correctly (30% and 16%, respectively) as among those who did not (14% and 6%). Multivariate analysis showed that correct assessment was positively associated with condom use; the association was driven by use among never-married individuals. Never-married males who assessed their risk correctly were 18% more likely than other males to report condom use; never-married females, 17% more likely than other females. CONCLUSIONS: Educational messages should aim at enabling individuals to correctly assess their own HIV risk and encouraging behavior change based on self-assessment of risk.