BACKGROUND: Bacterial vaginosis (BV) is a frequent cause of vaginal discharge that may be more common among women reporting sex with women (WSW). The objective of this study was to determine the prevalence of BV and predictors of infection among a sample of African American WSW. METHODS: African American WSW aged 18 years or older presenting to the Mississippi State Department of Health STD Clinic between 2009 and 2010 and reporting a history of sexual activity with a female partner during the preceding year were invited to participate. A survey on sexual history and sexual behavior characteristics was completed. Bacterial vaginosis was defined by Amsel criteria. Associations with participant characteristics were determined using logistic regression analysis. RESULTS: Bacterial vaginosis was diagnosed in 93 (47.4%) of 196 women. Bisexual identity (odds ratio [OR], 1.94; 95% confidence interval [CI], 1.03-3.66; P = 0.04), douching within the past 30 days (OR, 1.93; 95% CI, 1.09-3.43; P = 0.02), age 18 years or less at first sexual encounter with a female partner (OR, 3.18; 95% CI, 1.16-8.71; P = 0.02), and report of more than 1 lifetime male sexual partners (OR, 1.94; 95% CI, 1.01-3.74; P = 0.04) were significant predictors of BV in bivariate analysis. Bacterial vaginosis was less common among women who reported more than 1 lifetime female sexual partner (OR, 0.26; 95% CI, 0.09-0.76; P = 0.01). In multivariable analysis, age 18 years or less at first sex with a female partner approached significance, while report of 1 lifetime female sexual partner remained strongly associated with BV. CONCLUSIONS: Bacterial vaginosis was common in this sample of African American WSW and significantly associated with report of 1 lifetime female sexual partner. Copyright © 2013 American Sexually Transmitted Diseases Association. All rights reserved.