<p>Adverse childhood experiences (ACEs) are associated with long-term mental health difficulties, though the mechanisms linking types of adversity to psychopathology remain unclear. The Dimensional Model of Adversity and Psychopathology proposes that threat and deprivation influence development through distinct pathways. This study explored emotion regulation (ER) and executive functioning (EF) as mechanisms linking threat and deprivation ACEs to adolescent internalizing and externalizing symptoms. Participants (<i>N</i> = 4,898) were from the Future of Families and Child Wellbeing Study, a large, racially and socioeconomically diverse U.S. birth cohort. Cumulative exposure to threat and deprivation ACEs was measured between birth and age 5. ER and EF were assessed at age 5, and internalizing and externalizing symptoms at age 15 using multi-informant latent variables. Structural equation modeling tested direct and indirect paths while controlling for sociodemographic factors and baseline symptoms. Greater exposure to threat ACEs was associated with higher internalizing (β = 0.08, <i>p</i> &lt; .001) and externalizing symptoms (β = 0.10, <i>p</i> &lt; .001), whereas deprivation ACEs were only significantly associated with higher internalizing symptoms (β = 0.05, <i>p</i> = .01). ER mediated the paths between threat and internalizing (β = 0.04, <i>p</i> &lt; .001) and externalizing symptoms (β = 0.08, <i>p</i> &lt; .001) and between deprivation and internalizing (β = 0.01, <i>p</i> = .03) and externalizing symptoms (β = 0.01, <i>p</i> = .02). EF was not a significant mediator. Although direct links between ACEs and psychopathology differed by dimension, ER emerged as a common mechanism linking both threat and deprivation to adolescent psychopathology.</p>