Decades of research has identified alcohol use as a contributing cause of intimate partner aggression (IPA) perpetration; however, there have been fewer studies that seek to identify mediators of the relation between alcohol use and IPA perpetration. Building on research showing a positive association between problematic drinking and relationship dissatisfaction and relationship dissatisfaction and IPA, we examined whether relationship dissatisfaction accounted for the relation between problematic drinking and IPA perpetration in couples using statistical modeling that accounted for the interdependence between partners. Our results showed that (a) actor problematic drinking was related to actor psychological and physical IPA perpetration and that this relation was partially explained by actor relationship dissatisfaction, (b) partner problematic drinking was related to actor physical and psychological IPA perpetration and that this relation was partially explained by actor relationship dissatisfaction, and (c) partner problematic drinking was related to actor psychological IPA perpetration and that this relation was partially explained by partner relationship dissatisfaction. Together, our results highlight that when partner interdependence is considered, relationship dissatisfaction could be a potential mechanism of the alcohol-IPA association and provide some evidence for different pathways for psychological and physical aggression. (PsycInfo Database Record (c) 2020 APA, all rights reserved).