Childhood trauma and aggression were examined in 540 male prisoners. The Thus 540 male prisoners had a psychiatric interview, completed the Childhood Trauma Questionnaire (CTQ), and were assessed with the Brown-Goodwin Lifetime History of Aggression (BGHA) interview. There were significant correlations between CTQ scores and BGHA scores. Also prisoners with CTQ scores above the median had significantly higher BGHA scores than prisoners with CTQ scores below the median. Significantly more of the prisoners with CTQ scores above the median had more than one conviction, and significantly more had convictions as minors, and had exhibited violent behavior in prison. However, in logistic regression analyses that included possible confounding variables, CTQ scores related only to violence in prison while BGHA scores related to violent crime, having more than one conviction, conviction as a minor, and violence in prison. The relationship between CTQ and BGHA scores suggests the possibility that childhood trauma may be one determinant of aggression in prisoners.