Background and Aims: Large-scale neurocognitive brain networks are necessary to coordinate social cognition. Regions of prefrontal cortex that are key nodes in these networks are highly vulnerable to alcohol neurotoxicity, which may link poor social function and alcohol use disorder (AUD). However, there is very little research on how brain networks associated with social cognition are affected by AUD, and no studies of how these effects may differ between men and women. The current study aims to address this gap by examining the interaction between sex and AUD on the connectivity between brain networks implicated in social cognition.Methods: Matched groups of men and women with and without AUD (N=156; N=39/group) were selected from the Human Connectome Project. Resting-state functional magnetic resonance imaging data were used to compute functional connectivity between prefrontal networks, including default mode sub-networks (anterior dorsomedial: aDMN, ventromedial: vmDMN, temporal lobe: tDMN, and posterior DMN: pDMN), and central executive, dorsal attention, ventral attention, salience, and striatal networks. Between-network connectivity was assessed for interactions between sex, AUD diagnosis and symptom severity, and a measure of composite social cognition using non-parametric permutation testing, corrected for number of network pairs tested (Benjamini-Hochberg procedure, p<0.05 corrected). Results: Connectivity between aDMN–tDMN (AUDcontrols, pcor=.030) differed between groups. An interaction between sex and AUD symptom severity was significantly associated with aDMN–VAN (pcor= .032) connectivity. Social cognition scores were associated with aDMN–vmDMN connectivity (pcor=.003), with the relationship being moderated by sex, AUD-status, and symptom severity. Conclusions: This study addresses a critical gap in the literature on how brain network connectivity that underpins social cognition may be impaired in men and women with AUD. Our findings show that vulnerabilities emerge in men and women even at mild symptom severity and that there are significant sex differences, suggesting sex-specific treatment considerations are warranted.