The goal of this study is to examine the relations between histories of three types of sexual orientation victimization (childhood, personal, and institutional) and HIV sexual risk behavior among Black South African men who have sex with men (MSM). Secondarily, this study examines whether marijuana use and problem drinking mediate the relations. Participants were 125 Black MSM recruited from neighborhoods in Eastern Cape Province, South Africa. Questionnaires administered through audio computerized self-interviewing assessed sexual orientation victimizations, problem drinking and marijuana use, and unprotected anal sex with casual partners. Data were analyzed using multiple regression and multiple mediation modeling.Personal and institutional sexual victimizations were associated with condomless anal sex. Childhood sexual orientation victimization was positively associated with problem drinking. Neither problem drinking nor marijuana use mediated the relations between sexual orientation victimizations and having condomless anal sex with casual partners.