Mistrust among African Americans is often considered a potential source of racial disparities in HIV care. We sought to determine whether greater trust in one's provider among African-American patients mitigates racial disparities. We analyzed data from 1,104 African-American and 201 white patients participating in a cohort study at an urban, academic HIV clinic between 2005 and 2008. African Americans expressed lower levels of trust in their providers than did white patients (8.9 vs. 9.4 on a 0-10 scale; p < 0.001). African Americans were also less likely than whites to be receiving antiretroviral therapy (ART) when eligible (85% vs. 92%; p = 0.02), to report complete ART adherence over the prior 3 days (83% vs. 89%; p = 0.005), and to have a suppressed viral load (40% vs. 47%; p = 0.04). Trust in one's provider was not associated with receiving ART or with viral suppression but was significantly associated with adherence. African Americans who expressed less than complete trust in their providers (0-9 of 10) had lower ART adherence than did whites (adjusted OR, 0.40; 95% CI, 0.25-0.66). For African Americans who expressed complete trust in their providers (10 of 10), the racial disparity in adherence was less prominent but still substantial (adjusted OR, 0.59; 95% CI, 0.36-0.95). Trust did not affect disparities in receipt of ART or viral suppression. Our findings suggest that enhancing trust in patient-provider relationships for African-American patients may help reduce disparities in ART adherence and the outcomes associated with improved adherence.