Despite a reduction in newly acquired hepatitis B virus (HBV) infections since the mid-1980s, HBV remains an important cause of liver disease in the U.S. We report the prevalence of chronic HBV infection in a U.S. community and describe demographic and clinical characteristics. The Rochester Epidemiology Project records healthcare encounters of residents of Olmsted County, Minnesota. For all cases with a potential diagnosis of hepatitis B in this database, complete medical records were reviewed to identify subjects who met the inclusion criteria, i.e., a clinician diagnosis of chronic HBV infection and a laboratory record of positive hepatitis B surface antigen (HBsAg). There were 191 residents with chronic HBV infection in the community, consisting of 53% Asian, 29% African, 13% Caucasian, and 5% other or unknown race. The overall age- and sex-adjusted prevalence of HBV in this community was 0.15% in 2000. The race-specific prevalence was highest among Asians (2.1%), followed by African Americans (1.9%). The prevalence among Caucasians was 0.02%. Overall, 86% were born outside the U.S., 98% of whom were non-Caucasian. A total of 131 residents were tested for HBV replicative status, of whom 27% had viral replication. Of those tested for aminotransferases (n = 184), 28% had an abnormal value at least once. In a multivariable regression analysis, replicative status was the most influential (odds ratio [OR] = 5.98, P <.01) factor associated with abnormal aminotransferase values, followed by male gender (OR = 3.69) and age greater than 40 years (OR = 2.32 per decade). In conclusion, in this Midwestern community, chronic HBV infection was predominantly seen in immigrants from endemic parts of the world.