There is some evidence in the child welfare literature that child maltreatment is a risk factor for violent criminal behavior in adolescence, and that cumulative experiences of maltreatment may increase chances of delinquency. This current study was a secondary analysis of data gathered from participants who attended a school-based violence prevention program (n=1520; 655 control; 865 intervention) aimed at reducing violent delinquency. Questionnaires were administered at three different time points: baseline, post-intervention, and two year follow up. The control group received the standard curriculum, whereas the intervention group received curriculum targeting behaviours such as dating violence, unsafe sex, substance use and peer violence. Multi-level analyses revealed significant effects for both individual and school-level variables. The level of perceived safety was associated with a decrease in odds of committing violent delinquency. The study suggests that classroom based intervention may protect against engagement in delinquency for maltreated youth.