BACKGROUND:Medical mistrust, a result of systemic racism, is prevalent among Black Americans and may play a role in COVID-19 inequities. In a convenience sample of HIV-positive Black Americans, we examined associations of COVID-19 related medical mistrust with COVID-19 vaccine and COVID-19 treatment hesitancy, and negative impacts of COVID-19 on antiretroviral therapy (ART) adherence. METHODS:Participants were 101 HIV-positive Black Americans (ageM=50.3 years; SD=11.5; 86% cisgender male; 77% sexual minority) enrolled in a randomized controlled trial of a community-based ART adherence intervention in Los Angeles County, CA. From May to July 2020, participants completed telephone interviews on negative COVID-19 impacts, general COVID-19 mistrust (e.g., about the government withholding information), COVID-19 vaccine and treatment hesitancy, and trust in COVID-19 information sources. Adherence was monitored electronically with the Medication Events Monitoring System. RESULTS:Nearly all participants (97%) endorsed at least one general COVID-19 mistrust belief, and over half endorsed at least one COVID-19 vaccine or treatment hesitancy belief. Social service and healthcare providers were the most trusted sources. Greater COVID-19 mistrust was related to greater vaccine and treatment hesitancy b (SE)=0.85 (0.14), p<.0001 and b (SE)=0.88 (0.14), p<.0001, respectively. Participants experiencing more negative COVID-19 impacts showed lower ART adherence, assessed among a subset of 49 participants b (SE) = -5.19 (2.08), p = .02. DISCUSSION:To prevent widening health inequities, healthcare providers should engage with communities to tailor strategies to overcome mistrust and deliver evidence-based information, in order to encourage COVID-19 vaccine and treatment uptake.