We demonstrate the utility of cluster analysis for identifying diverse HIV risk groups found in a community-based sample. Within a group of 706 American Indian young adults, we used cluster analysis to identify four profiles of HIV risk/protection. The High Efficacy/Low Risk cluster had high levels of knowledge/education, self-efficacy, and outcome expectations about HIV protection, with low levels of risk behaviors. Low Efficacy/Low Risk had low levels of HIV knowledge/education, self-efficacy, and outcome expectations, but high levels of perceived risk for HIV with low levels of HIV risk behaviors. Low Efficacy/Moderate Risk was similar to the previous group, but its members had moderately higher levels of several risk behaviors and higher condom use. Low Efficacy/High Risk had high rates of several high-risk behaviors such as exchanging sex for money or injection drug use. Validation analyses highlighted differences that can be useful for the development of preventive interventions.