We used baseline data from a sample of African-American women living with HIV who were recruited to participate in a stigma-reduction intervention in Chicago and Birmingham (2013–2015) to (1) evaluate the relationship between HIV-related stigma and viral suppression, and (2) assess the role of depression and nonadherence to antiretroviral therapy (ART) as mediators. Data from women were included in this secondary analysis if they were on ART, had viral load data collected within 8-weeks of study entry and had complete covariate data. We used logistic regression to estimate the total effect of HIV-related stigma (14-item Stigma Scale for Chronic Illness) on viral suppression (< 200 copies/mL), and serial mediation analysis to estimate indirect effects mediated by depressive symptoms (8-item Patient Health Questionnaire) and ART nonadherence (number of days with missed doses). Among 100 women who met study inclusion criteria, 95% reported some level of HIV-related stigma. In adjusted models, higher levels of HIV-related stigma were associated with lower odds of being virally suppressed (AOR = 0.93, 95% CI = 0.89–0.98). In mediation analysis, indirect effects through depression and ART nonadherence were not significant. Findings suggest that HIV-related stigma is common among African-American women living with HIV, and those who experience higher levels of stigma are less likely to be virally suppressed. However, the mechanisms remain unclear.