Studies on early abstinence suggest that cognitive function is significantly reduced in the first year of abstinence, which raises the question of whether it is relevant to early relapse in patients with substance use disorders. This study investigates the extent to which impairments in executive function and memory predict alcohol relapse in patients with alcohol use disorder (AUD). Understanding these relationships is crucial for improving therapeutic approaches to prevent relapse in patients with AUD. We selected 116 adult patients (79 male and 37 female) diagnosed with AUD based on DSM-5 criteria, all of whom were undergoing alcohol detoxification treatment. A comprehensive array of neuropsychological tests was administered to assess global cognition, memory, and executive functions. Patients' alcohol use was monitored monthly during a 6-month follow-up period. Logistic regression and Cox regression were used to explore the relationship between cognitive function and the likelihood of alcohol relapse. Impairments in global cognition, semantic and phonemic fluency, cognitive flexibility, and learning ability during detoxification were significant predictors of relapse in AUD patients, showing similar predictive values at both 3 and 6 months post-treatment. An abnormal Montreal Cognitive Assessment (MoCA) score increased the risk of relapse by 123% (HR: 2.227), and impairments in both semantic and phonemic fluency each increased the risk by 142% (HR: 2.423). Additionally, abnormal performance on the MoCA, Trail Making Test Part B (TMT-B), and California Verbal Learning Test (CVLT) was associated with a higher number of drinking days at 3 months (IRR: 3.764; IRR: 2.237; IRR: 2.738, respectively) and abnormal MoCA and TMT-B scores at 6 months (IRR: 2.451; IRR: 1.859, respectively). The MoCA test is a valuable tool for predicting relapse risk in AUD patients undergoing detoxification treatment, with similar predictive value for relapse at 3 or 6 months. Learning ability needs to be assessed and their impairments considered in the treatment of AUD patients.Future research should explore strategies for managing patients with impairments in memory and learning ability to enhance treatment effectiveness and prevent relapse.