BACKGROUND: Few studies have examined associations between neighborhood social cohesion and sexual risk behaviors among gay, bisexual, and other sexual minority men (SMM), and none have among Black SMM in the southern U.S. The purpose of the current study is to examine associations between neighborhood social cohesion and sexual risk behaviors among Black SMM in the southern U.S., a population heavily impacted by HIV. We also examined whether these relationships are modified by religious participation for Black SMM in the southern U.S. METHODS: Data was obtained from the MARI Study, a sample of Black SMM ages 18-66 years, recruited from the Jackson, MS and Atlanta, GA metropolitan areas (n = 354). Neighborhood social cohesion was assessed with a validated 5-item scale. We conducted multivariable regression analyses to examine the association between neighborhood social cohesion with each of the sexual risk behaviors (e.g., condomless sex and drug use before or during sex), controlling for key confounders. We then performed moderation analysis by religious participation (religious attendance and private religiosity). RESULTS: Compared to Black SMM with higher perceived neighborhood social cohesion, Black SMM with lower neighborhood social cohesion had increased odds of alcohol use before or during sex (aPR = 1.56; 95% CI = 1.16-2.11) and condomless anal sex with casual partners (aPR = 1.55; 1.03-2.32). However, the magnitude of these associations varied by religious attendance and private religiosity. Black SMM with low religious service attendance had higher risk of alcohol use in the context of sex when perceived neighborhood social cohesion was low; those with high private religiosity had elevated alcohol use in the context of sex when perceived neighborhood social cohesion was low. DISCUSSION: Interventions that target connectedness among neighborhood members through community education or mobilization efforts, including the involvement of religious organizations, should be considered for HIV prevention focused on alcohol and condomless sex among Black SMM.