African Americans purportedly have a higher prevalence of mental illnesses but are often misdiagnosed and less likely to seek treatment. Delayed treatment has been associated with the stigma related to these disorders. The demographic characteristics, length of stay, most prevalent psychiatric diagnoses, and hospital admissions of African Americans were compared to other U.S. populations using a nationwide sample (N = 4,474,732). African American participants were younger, had significantly longer lengths of stay, and were admitted more often through the emergency room than the other groups in this sample. Psychosis, alcohol/drug dependence, and depressive neurosis were the most prevalent psychiatric diagnoses reported for African American participants. Research is needed to explain these results so that strategies can be instituted to improve the poor mental health outcomes often observed in African American populations.