Experienced childhood trauma (CT) is prevalent in individuals with alcohol use disorders (AUDs). Few studies examine how experienced CT affects alcohol-treatment outcome. This study accordingly investigates whether experienced CT independently affects treatment outcome 2.5- and 5-years post-treatment, controlling for other significant variables, such as self-efficacy, self-directedness, and mental health. Participants (n = 349) with AUDs (without severe psychiatric comorbidity or drug dependence) were recruited from three alcohol-treatment settings and followed up 2.5- and 5 years after treatment initiation. The group with experienced CT had more mental health problems, less self-efficacy, and less self-directedness. Multiple and logistic regressions were conducted using the outcome variables total number of DSM-IV criteria and abstinence. The results indicated that CT did not independently affect treatment outcome. Individuals with AUDs and experienced CT benefitted the same from alcohol treatment as those without such experience; however, studies should also examine groups with AUD and psychiatric comorbidity.