This paper examines the cumulative prevalence of victimization and its impact on mental health in a nationally representative sample of 2030 children aged 2-17 in the USA. Telephone interviews conducted with both caregivers and youth revealed socio-demographic variations in lifetime exposure to most forms of victimization, with ethnic minorities, those lower in socio-economic status, and those living in single parent and stepfamilies experiencing greater victimization. Sexual assault, child maltreatment, witnessing family violence, and other major violence exposure each made independent contributions to levels of both depression and anger/aggression. Other non-victimization adversities also showed substantial independent effects, while in most cases, each victimization domain remained a significant predictor of mental health. Results suggest that cumulative exposure to multiple forms of victimization over a child's life-course represents a substantial source of mental health risk.