Objectives. To examine the effects of within-neighborhood and neighboring characteristics on discrimination, stigma, mental health, and HIV outcomes among Black women living with HIV (BWLWH). Methods. A total of 151 BWLWH in a southeastern US city provided baseline data (October 2019‒January 2020) on experienced microaggressions and discrimination (race-, gender-, sexual orientation-, or HIV-related), mental health (e.g., depression, posttraumatic stress disorder), and HIV outcomes (e.g., viral load, antiretroviral therapy adherence). Neighborhood characteristics by census tract were gathered from the American Community Survey and the National Center for Charitable Statistics. Spatial econometrics guided the identification strategy, and we used the maximum likelihood technique to estimate relationships between a number of predictors and outcomes. Results. Within-neighborhood and neighboring characteristics (employment, education, crime, income, number of religious organizations, and low-income housing) were significantly related to intersectional stigma, discrimination, mental health, HIV viral load, and medication adherence. Conclusions. Policy, research, and interventions for BWLWH need to address the role of neighborhood characteristics to improve quality of life and HIV outcomes. (Am J Public Health. 2022;112(S4):S433-S443. https://doi.org/10.2105/AJPH.2021.306675).