Cigarette smoking is particularly harmful for sexual minority men living with HIV. This study aimed to find benefits of quitting by examining relationships between smoking and sustained HIV RNA suppression, recent CD4 count, ART medication adherence, and engagement in HIV medical care. Sexual minority men (n = 346), former or current smokers, received HIV care at a community health center. Survey responses were combined with electronic health record data in adjusted regression models. Most patients were Caucasian (87%) and 148 (46%) had incomes below the poverty level and 80% had sustained HIV RNA suppression. Compared to current smokers, former smokers had increased odds of sustaining HIV RNA suppression (OR 1.89; 95% CI 1.02–3.48) of reporting > 90% adherence (OR 2.25; 95% CI 1.21–4.17), and were less likely to miss appointments (OR 0.37; 95% CI 0.17–0.82). Heavier smokers (OR 0.36; 95% CI 0.17–0.77) and patients who smoked the longest (OR 0.31; 95% CI 0.14–0.68) had reduced odds of sustaining HIV RNA suppression. Smoking assessment, treatment, and referral could augment HIV outcomes for sexual minority men with HIV.