Adverse childhood experiences (ACEs) are robustly associated with physical and mental health problems over the life span. Relatively limited research has examined the breadth of ACEs among military veteran populations, for whom ACEs may be premilitary traumas associated with suicidal ideation and attempt. Using data from the Comparative Health Assessment Interview Research Study, a large national survey sponsored by the U.S. Department of Veterans Affairs, this investigation examined the prevalence of 22 self-reported potentially traumatic experiences before the age of 18 (i.e., ACEs) among veterans and nonveterans and estimated the association of ACEs with suicidal ideation and attempt at age 18 or older. All analyses were weighted to account for complex sampling design and stratified by gender. The study sample included 9,571 veteran men, 3,143 nonveteran men, 5,543 veteran women, and 1,364 nonveteran women. Veteran men reported greater average frequency of ACEs than nonveteran men (2.7 ACEs vs. 2.3 ACEs, respectively, p < .001); 11.1% of veteran men indicated >6 ACEs compared with 7.3% of nonveteran men (p < .001). Veteran women reported greater average frequency of ACEs than nonveteran women (3.1 ACEs vs. 2.4 ACEs, respectively, p < .001). Among women, more veterans than nonveterans reported >6 ACEs (14.9% vs. 8.6%, respectively, p < .001). The strongest correlate of suicide attempt at age 18 or older for veteran men was having >6 ACEs (adjusted odds ratio, aOR = 4.20, 95%CI = 2.72-6.49); for veteran women, the strongest correlate was suicidal ideation or attempt before age 18 (aOR = 5.37, 95%CI = 4.11-7.03). Suicide prevention research, policy, and practice should address ACEs among veterans as salient premilitary risk factors. (PsycInfo Database Record (c) 2021 APA, all rights reserved).