<p>The present study investigates the mediating role⁠ of ⁠psychological ⁠flexibility in the relationship between adverse childhood experiences (ACEs), positive childhood experiences (PCEs), and suicidal thoughts⁠ among emerging adults. The sample comprised 559 individuals aged between 18 and 24 years (M_age = 21.89, SD_age = 2.17), including 415 women (74.15%) and 144 men (25.85%). Participants⁠ completed the Adverse Childhood Experiences Scale, the Positive Childhood Experiences Scale, the Brief Suicide Cognitions Scale (BSCS), the Acceptance and Action Questionnaire⁠-II (AAQ-II), and a⁠ demographic information form. Data were analysed using Hayes’s PROCESS macro⁠ for SPSS (Model 4) with 5.000 bootstrap samples. The results revealed a significant positive association between ACEs and suicidal thoughts. In addition, PCEs were negatively associated with suicidal thoughts. Psychological flexibility was negatively related to suicidal thoughts and partially mediated the relationship between ACEs, PCEs, and suicidal thoughts. These findings highlight the dual role of childhood experiences on suicidal cognition, indicating that adverse experiences function as a risk marker, whereas positive experiences serve as protective factors. Importantly, the findings should not be interpreted as implying that childhood experiences can be retrospectively altered in adulthood. Rather, ACEs and PCEs function as developmental risk and protective markers, whereas psychological flexibility represents a modifiable and clinically actionable intervention target. From this perspective, interventions⁠ aimed at enhancing psychological flexibility—such as⁠ Acceptance and Commitment Therapy–informed approaches—may be associated with reduced suicidal risk among emerging adults with⁠ elevated exposure to childhood adversity. Future research should extend this model by examining the interactive effects of ACEs and PCEs and by testing psychological flexibility as a potential moderating variable using longitudinal designs.</p>