The prevalence of cigarette smoking and the relations between smoking and HIV clinical markers, HIV medication adherence, and opportunistic infections (OIs) were examined in a sample of 199 HIV+, gay, bisexual, and other men who have sex with men (MSM) aged 50 and older. Overall, 35.7% were current smokers, 35.7% were former smokers, and 28.6% were never smokers. In the final multivariable polytomous logistic regression model controlling for age, income, and illicit drug use, current smokers were less likely to report an undetectable viral load as compared to never and former smokers. Relative to never smokers, former smokers were more likely report respiratory OIs, and current smokers were more likely to report gastrointestinal OIs. This study demonstrates high prevalence of cigarette smoking among aging, HIV+ MSM and provides additional evidence for a relationship between smoking and poorer HIV clinical markers. Targeted and tailored smoking cessation programs within the context of HIV care services are warranted.