This study tested four health beliefs, as postulated by the Health Belief Model, in terms of their capacity to predict sexual monogamy, condom use, and overall changes in health behavior in the context of HIV prevention. Four research hypotheses were proposed. The first, second, and third research hypotheses predicted a positive relationship between health beliefs associated with susceptibility, severity, and benefits, and HIV-preventive behavior, respectively. the fourth hypothesis postulated a negative relationship between health beliefs associated with barriers and HIV-preventive behavior. Research findings indicated that perceived susceptibility and barriers were significant predictors of the adoption of certain HIV-preventive behaviors among sexually-active young adults. In particular, susceptibility was a significant predictor of monogamy while barrier significantly predicted monogamy and overall changes in health behavior. Implications of the results and future research needs are discussed.