We examine the effect of perceived school fairness on one’s likelihood of participating in school violence and how social support influences this relationship. General strain theory (GST) and procedural justice theory suggest that when students perceive unfairness in school rules or treatment from teachers, they will be more likely to participate in violence. GST proposes that the strength of these relationships may be reduced by social support. Data from the 2009 School Crime Supplement of the National Crime Victimization Survey show that students who perceive unfair treatment from teachers are more likely to bring a weapon to school and fight at school than are students who believe that their teachers are fair. Students who perceive that rules are unfair are more likely to bring a weapon to school than are students who believe rules are fair. Perceived support from adults at school reduces the impact of teacher/rule unfairness on school violence.