Problematic alcohol use is a prevalent issue among college students in the United States, leading to negative consequences such as lower academic performance, unintentional injuries, and depression (Porter & Pryor, 2007; Patrick et al., 2020). According to an integrative motivational model, an individual’s broader context and momentary context both contribute to motives for substance use (Votaw & Witkiewitz, 2021), which are widely regarded as the “final common pathway” influencing alcohol use (Cooper, 1994). Chapter 1 reviewed biological, psychological, and social mechanisms linking ACEs to substance use problems, highlighting emotion regulation difficulties and drinking motives as key psychological pathways. Building on this framework, Chapter 2 investigated whether state emotion regulation difficulties mediate the relationship between adverse childhood experiences (ACEs) and state internal drinking motives (coping and enhancement), and whether gender moderates the relationship between state emotion regulation difficulties and both state internal drinking motives in the second stage of the mediation. Using a single-session laboratory design with a sample of undergraduate active drinkers (N = 337; analytic N = 317), participants watched emotion-elicit film clip followed by assessments of state emotion regulation difficulties and state drinking motives. Results indicated that state emotion regulation difficulties significantly mediated the association between ACEs and coping motives for drinking, but not enhancement motives. Gender did not moderate the indirect pathway for either motives type. The study’s findings highlight the importance of emotion regulation difficulties as a mechanism linking childhood adversity to drinking to cope motive. For college drinking intervention, efforts should include emotion regulation skill building and motivational approaches, especially for those with ACE histories.