This study aimed at investigating the degree to which relational adverse childhood experiences (ACEs) would affect suicide outcomes during early and young adulthood of Iranian female and male students. In all, 487 undergraduate students (59.2% females) with a mean age of 20.66 ± 1.42 were recruited using a multistage clustering sampling method from eight schools from the fields of humanities, engineering, and basic sciences. Suicide Behavior Questionnaire–Revised form (SBQ-R) was employed for assessing past year suicidal ideation (PYSI, once or more), the meaningful likelihood of future suicide (mLoFS, a score of 2 or more), and suicide risk (SR ≥7). Relational ACEs were assessed in the form of a yes/no question, including caregivers’ maltreatment, household relational dysfunction, family loss events, school events, and sexual abuse. Analyses were conducted using Fisher’s exact test, chi-square test, and univariate binary logistic regression. The rates of PYSI, LoFS, and SR were, respectively, 37.2%, 44.6%, and 30.8%. The most experienced event was witnessing verbal violence (68.8%) and the least was divorce/separation (6.2%). All the events and domains (except family loss events), the interaction of domains, and cumulative events significantly increased the odds of suicide outcomes, in which females were more affected by all types of relational ACEs. Students whose ethnicity was Azari & Turk and who were studying in humanities or basic sciences showed a higher suicide risk than their counterparts. The study showed that the rates of relational ACEs and suicide outcomes were remarkable, in Iran. Because of the detrimental effects of relational ACEs on suicidality, mostly for females, it is necessary to improve the initiatives promoting child protection and legal support for health professionals to address child abuse. There is also an urgent need for providing young students with supports and effective interventions.