The frequency of HIV infection is increasing in men who have sex with men (MSM) aged 40 and older yet little is known about factors that influence their risky sexual behavior, such as sexual positioning. The goal of this study was to examine multi-level factors associated with unprotected receptive anal intercourse (URAI) and unprotected insertive anal intercourse (UIAI) in MSM aged 40 and older. A community-based sample of 802 self-identified MSM aged 40-94 years was recruited through targeted outreach from community venues (e.g., bars, social events) in South Florida and completed an anonymous pen-and-paper questionnaire. Logistic regression showed that younger age (i.e., aged 40-59; odds ratio [OR]=0.6; 95% confidence interval [CI]: 0.4, 0.9), HIV-positive status (OR=2.8; 95% CI: 1.9, 4.0), drug use (OR=2.6; 95% CI: 1.7, 3.7), a larger number of male sexual partners (OR=1.7; 95% CI: 1.3, 2.3), and lower scores on internalized homonegativity (OR=0.9; 95% CI: 1.0, 1.0) were associated with higher risk for URAI. Younger age (OR=0.4; 95% CI: 0.3, 0.6), HIV-positive status (OR=1.5; 95% CI: 1.0, 2.1), drug use (OR=1.6; 95% CI: 1.1, 22.3), Viagra use (OR=1.7; 95% CI: 1.2, 2.4), larger number of sexual partners (OR=2.1; 95% CI: 1.6, 2.9), and holding views more characterized by high optimism concerning the future (OR=1.1; 95% CI: 1.0, 1.1) were associated with higher risk for UIAI. These results provide useful information that may guide the development of tailored prevention interventions to reduce the growing rates of HIV among MSM aged 40 and older.