To date, no studies have reported the use of text messaging to deliver cognitive behavioral therapy (CBT) to alcohol users with HIV. We developed and evaluated a text messaging-based program to deliver CBT targeting both alcohol use and adherence to antiretroviral (ART) medications for adults with alcohol use disorders and comorbid HIV. Participants were randomly assigned to receive either a 12-week CBT-based text messaging intervention (ALC-TXT-CBT) targeting ART adherence and alcohol use (n = 18); or an informational pamphlet (INFO) comprising educational content focused on alcohol use and medication adherence (n = 17). ART adherence and alcohol use were compared for those in ALC-TXT-CBT to INFO across baseline and 12-week (i.e., treatment-end) assessments using mixed model regression analyses and paired t-tests. Relative to those in INFO, ALC-TXT-CBT participants evidenced increases in ART adherence, measured by phone-based unannounced pill counts (β = .16, p = .04), and biochemically by viral load (t = -2.0, p = .04) at treatment-end. ALC-TXT-CBT participation was also associated with reductions in heavy drinking at treatment-end (t = 2.7, p = 0.02), while overall alcohol use frequency did not differ significantly between groups (t = 1.5, p = 0.07). Findings demonstrated promising preliminary evidence for the efficacy of ALC-TXT-CBT in improving medication adherence and reducing heavy alcohol use among individuals with alcohol use disorders and comorbid HIV infection.Trial registrationThis trial was registered with ClinicalTrials.gov, NCT02603471.