Objective: The objective of this study was to examine nonmedical stimulant use among fraternity/sorority members and nonmembers and whether psychological variables (e.g., internal restlessness, depression, anxiety, and stress) were related to nonmedical stimulant use. Method: The sample consisted of 1,033 undergraduate students from five universities located in the northeastern, southeastern, northwestern, southwestern, and midwestern regions of the United States. Results: The findings revealed that fraternity and sorority members reported a higher rate of nonmedical stimulant use than nonmembers. In addition, regression analyses revealed that higher ratings of anxiety, stress, internal impulsivity, and internal restlessness significantly predicted nonmedical stimulant use. Conclusion: Current findings support further examination of nonmedical stimulant use among other college student subpopulations (i.e., athletic teams, honor societies, residence halls). In addition, there is a strong need to develop research-based intervention and preventive measures that target college populations identified as being at risk for nonmedical stimulant use. (Contains 3 tables.)