We compared the demographics and clinical characteristics of HIV-infected patients with and without hepatitis C virus (HCV) coinfection hospitalized at Cook County Hospital, Chicago, Illinois, from October 1999 through September 2000. Two hundred three (40%) of the 510 patients were coinfected with HCV. HCV coinfected patients were less likely to be on highly active antiretroviral therapy (HAART) and were frequently hospitalized with higher CD4 counts for non-HIV-related medical problems including complications of liver disease.