Orphans and separated children (OSC) are a vulnerable population whose numbers are increasing, particularly in sub-Saharan Africa and Asia. Over 153 million children worldwide have lost one or both parents, including 17 million orphaned by AIDS, and millions more have been separated from their parents. As younger orphans enter adolescence, their sexual health and HIV-related risk behaviors become key considerations for their overall health. Importantly, their high prevalence of exposure to potentially traumatic events (PTEs) may put OSC at additional risk for adverse sexual health outcomes. The Positive Outcomes for Orphans study followed OSC randomly sampled from institution-based care and from family-based care, as well as a convenience sample of non-OSC, at six sites in five low-and middle-income countries. This analysis focused on the 90-month followup, during which adolescents 16 and older were assessed for sexual health, including age at sexual debut, past-year sex, past-year condom use, and perceptions of condom use. We specifically examined the relationship between PTEs and sexual health outcomes. Of the 1258 OSC and 138 non-OSC assessed, 11% reported ever having sex. Approximately 6% of participants reported recent sex and 5% reported having recent unprotected sex. However, 70% of those who had recent sex reported that they did not use a condom every time, and perceptions of condom use tended to be unfavorable for protection against sexual risk behavior. Nearly all (90%) of participants reported experiencing at least one lifetime PTE. For those who experienced “any” PTE, we found increased prevalence of recent sex (PR = 1.39 [0.47, 4.07]) and of recent unprotected sex (PR = 3.47 [0.60, 19.91]). This study highlights the need for caregivers, program managers, and policymakers to promote condom use for sexually active OSC and identify interventions for trauma support services. Orphans living in family-based care may also be particularly vulnerable to early sexual debut and unprotected sexual activity.