This article contributes new evidence on the associations among immigrant generation, gender, and sexual risk behavior among Latino adolescents in the United States. Longitudinal data from 3,272 Latino adolescents (grades 7-12) who participated in the National Longitudinal Study of Adolescent Health (Add Health) were examined for evidence of the immigrant paradox in sex risk behaviors. Compared to more acculturated counterparts, first generation adolescents demonstrated the lowest levels of sexual risk behavior at each time point across adolescence and early adulthood. Gender significantly predicted change in sexual risk behavior over time with Latina females displaying a significantly greater increase in sexual risk behavior than males. Results indicate that third generation Latino adolescents and Latina females, in particular, may benefit from targeted sexual risk interventions to prevent increases in sex risk behavior during adolescence. (Contains 4 tables.)