The present study tested whether attitudes toward violence mediate the association between intimate partner violence exposure and antisocial behavior across adolescence, and whether cortisol level moderates these pathways in an ethnically diverse sample of 190 boys from low-income, urban families. Results suggest that a pathway from intimate partner violence exposure at age 12 to antisocial behavior at age 17 is explained by pro-violence attitudes at age 15. Boys with greater exposure to intimate partner violence endorsed stronger pro-violence attitudes, which predicted increases in antisocial behavior. Further, the pro-violence attitudes to antisocial behavior pathway was stronger among boys with heightened versus dampened cortisol levels. Results suggest that violent attitudes are important for understanding the cognitive underpinnings of antisocial behavior following intimate partner violence exposure, particularly in youth with high cortisol levels. Implications for prevention and intervention are discussed with respect to targeting malleable child behavior linked to later antisocial behavior.