BACKGROUND: We investigated the feasibility, acceptability, safety, and preliminary effectiveness of the Counselling for Alcohol Problems (CAP) psychological intervention delivered by non-specialist health workers (NSHW) to participants with alcohol use disorder (AUD) and comorbid depression in primary care. METHODS: We used data from a single blind randomised controlled trial conducted in ten primary health care centres in Goa, India. Adult male harmful or dependent drinkers with or without depression were randomized (1:1) to receive either CAP & enhanced usual care (EUC) or EUC only. Process indicators such as the number of completed counselling sessions were assessed and compared between comorbid and non-comorbid participants. Remission from AUD and depression along with abstinence were measured at 3 and 12 months post randomisation. Analyses were on an intention-to-treat basis, employing multivariable regression analyses. RESULTS: 271 participants had symptoms of comorbid depression; 241 did not. Both groups completed a similar number of counselling sessions (adjusted Mean Difference 0.05, 95 %CI -0.24-0.34;p = 0.72). Among comorbid participants, CAP did not lead to more frequent adverse events compared to EUC only (adjusted Odds Ratio [aOR] 0.84, 0.43-1.64;p = 0.62), and there was no evidence for an effect of CAP on remission from AUD or depression at 3 months (aOR 1.51, 0.84-2.74;p = 0.17 and aOR 0.74, 0.43-1.27;p = 0.28) and 12 months follow-up, respectively (aOR 1.69, 0.96-3.01;p = 0.08 and aOR 1.08, 0.62-1.87;p = 0.79). CONCLUSIONS: Brief therapies like CAP can be safely delivered by NSHWs to patients with comorbid AUD and depression, but their effectiveness may be limited and requires further investigation.