Objective: Adverse childhood experiences (ACEs) are associated with increased risk for suicide and appear to occur in disproportionately high rates among men who served in the U.S. military. However, research has yet to examine a comprehensive range of ACEs among Iraq/Afghanistan veterans with combat-related posttraumatic stress disorder (PTSD) or whether these premilitary stressors may contribute to suicidal behavior in this highly vulnerable population. Method: A sample of 217 men entering a residential program for combat-related PTSD completed measures for ACEs, combat exposure, and lifetime suicidal ideation and attempts. Results: The majority of patients had experienced multiple types of adversity or traumas during childhood/adolescence. In particular, 83.4% endorsed at least 1 ACE category and 41.5% reported experiencing 4 or more ACEs. When accounting for effects of deployment-related stressors, we further found that accumulation of ACEs was uniquely linked with thoughts of suicide or attempts among these patients. Namely, for every 1-point increase on the ACE Questionnaire, veterans’ risk of suicidal ideation and attempts increased by 23% and 24%, respectively. Conclusion: This brief report provides initial evidence that veterans seeking treatment for combat-related PTSD often have extensive histories of premilitary stressors that may increase suicide risk beyond probable deployment-related traumas.