Youth enrolled in dropout prevention and alternative school programs engage in a number of high risk behaviors in greater numbers than those in traditional school settings [1, 2]. However, data on alcohol and drug use influences and risky sexual behavior are often not collected or reported among these youth due to small enrollments and rapid turnover. In this study alcohol and drug use and sexual behaviors were surveyed among 212 youth in dropout prevention. A risk profile score for HIV/AIDS was developed and the contribution of alcohol and drug use to HIV/AIDS risk was determined. Results showed that use of alcohol and drugs and age of sexual initiation were significantly associated with a high risk profile score. Of sexually active youth, 28 percent reported using alcohol or drugs prior to having sexual intercourse and more than half reported not using condoms during their last sexual experience. Males were more likely than females to use alcohol and drugs before having sex, and were more likely to have had sex with two or more partners. Findings from this study suggest that among youth in dropout prevention, the association of alcohol and drug use to HIV/AIDS risk is significant and that prevention programs need to target alcohol and drug use as important influences on risky sexual behavior.