There is convincing evidence that trauma-related psychological distress and aggressive behavior are highly related among adolescents. The evidence is less clear regarding the direction of this relation. Objective: The purpose of this study was to examine reciprocal longitudinal relations between trauma-related distress and physical aggression. Method: A predominantly African American sample of early adolescents (N = 2,271; mean age = 12.9) living in an urban, under-resourced community participated in this investigation. The current study used autoregressive cross-lagged models to examine changes across four waves of data within each grade of middle school. Results: Support was found for trauma-related distress uniquely predicting increased levels of physical aggression. This effect was consistent across gender and within and across middle school grades. Conversely, physical aggression did not predict changes in trauma-related distress. Conclusions: Violence prevention efforts should routinely screen for trauma-related distress.