Objective: Early victimization elevates children's risk for developing psychopathology. Recent findings suggest that disruptions in developmental processes related to symptoms of posttraumatic stress (PTS) may partially account for the association between early victimization and subsequent psychopathology. The present study prospectively tested the temporal sequencing of these associations using, multiinformant measurements in a large, diverse sample of children at high risk for victimization. Method: This study measured victimization (i.e., direct, indirect, familial, and nonfamilial violence), PTS, externalizing, and internalizing problems among 1154 children (561 girls and 593 boys) who participated in the Longitudinal Studies of Child Abuse and Neglect (LONGSCAN). Results: Structural equation modeling revealed that, in addition to directly impacting psychopathology, childhood victimization contributed to escalations in internalizing and externalizing problems as children transitioned from middle to late childhood indirectly through PTS. The mediational role of PTS was largely similar for girls and boys and for those who were investigated for early reports of maltreatment and those identified early as at-risk for victimization. Conclusions: This study delineated the role of PTS in the development of psychopathology following early victimization. These findings highlight the importance of carefully assessing for underlying trauma symptoms when considering diverse presentations of psychopathology among youth who have been victimized.