Using the 1995 new cohort of the National Survey of Adolescent Males, this paper examines the association between perceptions of child support and adolescent males' sexual activity. The results indicate that adolescent males who expect the chance of being required to pay child support is high if one becomes a non-resident father or who has a family member who paid child support before are more likely to have the same female sexual partner and less likely to have had two or more female partners. Additionally, expectations of being required to pay child support and history of a family member paying child support are positively associated with contraceptive use, especially for Black adolescents.