Meta-analyze the literature on posttraumatic stress (PTS) symptoms in youths post-disaster. Meta-analytic synthesis of the literature (k = 96 studies; Ntotal = 74,154) summarizing the magnitude of associations between disasters and youth PTS, and key factors associated with variations in the magnitude of these associations. We included peer-reviewed studies published prior to 1/1/2009 that quantitatively examined youth PTS (≤ 18 years at event) after a distinct and identifiable disaster. Despite variability across studies, disasters had a significant effect on youth PTS (small-to-medium magnitude; rpooled = .19, SEr = .03; d = 0.4). Female gender (rpooled = .14), higher death toll (disasters of death toll ≤ 25: rpooled = .09; vs. disasters with ≥ 1,000 deaths: rpooled = .22), child proximity (rpooled = .33), personal loss (rpooled = .16), perceived threat (rpooled = .34), and distress (rpooled = .38) at time of event were each associated with increased PTS. Studies conducted within 1 year post-disaster, studies that used established measures, and studies that relied on child-report data identified a significant effect. Youths are vulnerable to appreciable PTS after disaster, with pre-existing child characteristics, aspects of the disaster experience, and study methodology each associated with variations in the effect magnitude. Findings underscore the importance of measurement considerations in post-disaster research. Areas in need of research include the long-term impact of disasters, disaster-related media exposure, prior trauma and psychopathology, social support, ethnicity/race, prejudice, parental psychopathology, and the effects of disasters in developing regions of the world. Policy and clinical implications are discussed.