This study examined the relationship of cardiovascular reactivity to both interpersonal mistreatment and discrimination in a community-based sample of African American and European American women (N=363) in midlife. Subtle mistreatment related positively to diastolic blood pressure (DBP) reactivity for African American participants but not their European American counterparts. Moreover, among the African American participants, those who attributed mistreatment to racial discrimination exhibited greater average DBP reactivity. In particular, these women demonstrated greater DBP reactivity to the speech task, which bore similarities to an encounter with racial prejudice but not to a nonsocial mirror tracing task. These findings are consistent with the hypothesis that racial discrimination is a chronic stressor that can negatively impact the cardiovascular health of African Americans through pathogenic processes associated with physiologic reactivity.