Background <p>Parents’ adverse childhood experiences (ACEs) are associated with poorer mental health and elevated parenting stress, which could increase their children’s risk of ACE exposure. Accordingly, understanding the mechanisms underlying the intergenerational transmission of ACEs is crucial for breaking this cycle.</p> Objective <p>Based on family systems theory and parenting stress model, this study aims to explore the sequential mediating role of parental depressive symptoms and parenting stress in the association between parental ACEs and adolescents’ ACEs.</p> Methods <p>This cross-sectional study investigated 1479 Chinese families. Fathers and mothers completed self-report questionnaires assessing ACEs, depressive symptoms, and parenting stress independently, while their children (adolescents) filled out the ACEs assessment questionnaire only.</p> Results <p>This study found that both paternal and maternal ACEs had total effects on adolescents’ ACEs. In addition, maternal ACEs were indirectly associated with adolescents’ ACEs via maternal parenting stress. Moreover, both paternal and maternal ACEs were associated with maternal, but not paternal, depressive symptoms and parenting stress, which in turn contributed to adolescents’ ACEs.</p> Conclusions <p>Targeting maternal depressive symptoms and parenting stress may offer a feasible entry point to interrupt intergenerational ACE transmission. These findings support school-based integrated screening and referral for students and caregivers, with attention to maternal depression and parenting stress.</p>