ObjectivesLittle is known about whether distress tolerance and anxiety mediate the relationship between comorbid complex posttraumatic stress disorder (CPTSD) and alcohol use among military veterans. Here, we investigated the contribution of distress tolerance and anxiety on the strength of the CPTSD and alcohol use association. We hypothesized that the impact of a two‐factor model of CPTSD derived from subscale scores on the International Trauma Questionnaire (ITQ)—namely ITQ PTSD and ITQ Disturbances in Self Organization (DSO; e.g., issues with affective regulation/self‐belief and shame)—on alcohol use severity would be mediated by anxiety but not by distress tolerance.MethodsParticipants included 403 community‐dwelling United Kingdom (UK) veterans (91.64% male, Mage = 51.15 years, SD = 12.48) recruited as part of a larger, online study.ResultsFindings indicated that the influence of CPTSD symptoms on alcohol use severity was mediated by anxiety, not by distress tolerance, with greater relative impact due to ITQ DSO status than ITQ PTSD status.ConclusionsWe identified the mediational influence of anxiety and distress tolerance on the association between CPTSD subscales and alcohol use in UK veterans. Interventions for anxiety may be adapted for reducing problematic alcohol use and the impact of CPTSD symptoms in veterans with comorbid PTSD and alcohol use disorder.