Knowledge of sexual partners' HIV infection can reduce risky sexual behaviors. Yet, there are no published studies to-date examining prevalence and characteristics associated with knowledge among African-American women living in high poverty communities disproportionately affected by HIV. Using the HIV Prevention Trial Network's (HPTN) 064 Study data, multivariable logistic regression was used to examine individual, partner, and partnership-level determinants of women's knowledge (n = 1,768 women). Results showed that women's demographic characteristics alone did not account for the variation in serostatus awareness. Rather, lower knowledge of partner serostatus was associated with having two or more sex partners (OR = 0.49, 95 % CI 0.37-0.65), food insecurity (OR = 0.68, 95 % CI 0.49-0.94), partner age >35 years (OR = 0.68, 95 % CI 0.49-0.94), and partner concurrency (OR = 0.63, 95 % CI 0.49-0.83). Access to financial support (OR = 1.42, 95 % CI 1.05-1.92) and coresidence (OR = 1.43, 95 % CI 1.05-1.95) were associated with higher knowledge of partner serostatus. HIV prevention efforts addressing African-American women's vulnerabilities should employ integrated behavioral, economic, and empowerment approaches.