This study investigated racial differences in patient-physician communication around mental health versus biomedical issues. Data were collected from audiorecorded periodic health examinations of adults with mental health needs in the Detroit area (2007-2009). Patients and their primary care physicians conversed for twice as long, and physicians demonstrated greater empathy during mental health topics than during biomedical topics. This increase varied by patient and physician race. Patient race predicted physician empathy, but physician race predicted talk time. Interventions to improve mental health communication could be matched to specific populations based on the separate contributions of patient and physician race.