The main aim of this study was to examine the relation between perceived friend intervention and individual-level bullying and intervention. The mediating role of beliefs about aggression and attitudes toward victims was also investigated. One hundred eighteen students (49 boys and 69 girls) in grades 6 to 8 completed a questionnaire that included items measuring bullying, intervention, beliefs about aggression, and attitudes toward victims. The results of the multilevel analysis revealed that children in friendship groups with low levels of perceived friend intervention were less likely to intervene, but were not more likely to bully. Attitudes toward victims and normative beliefs about aggression did not mediate a relation between perceived friend intervention and individual intervention and bullying. Self-reported bullying had a moderate negative correlation with positive attitudes toward victims and a positive correlation with beliefs about aggression. Propensity to intervene had a moderate positive correlation with positive attitudes toward victims and a small negative correlation with positive beliefs about aggression. Although the mediation model tested in the current study was not supported, this study provides a foundation for studying group-level processes that may influence children's intervention in bullying situations.