Bovine coronavirus (BCoV) is a causative agent of entero-pathogenic diarrhea in young calves and winter dysentery (WD) in adult cattle. In this study, we conducted a nationwide sero-epidemiological survey of BCoV infection in Korea. In total, 3,029 bovine sera collected between October and December 2005 were screened for the presence of antibodies against BCoV using a hemagglutination inhibition (HI) test. Half (50.0%) of individual cattle tested were positive for BCoV. The regional distribution of the seroprevalence of positive HI antibodies was 55.7% (234/420) in Gyeonggi, 53.0% (316/596) in Jeonra, 51.9% (374/720) in Chungcheong, 48.5% (401/827) in Gyeongsang, 43.9% (79/180) in Jeju, and 38.1% (109/286) in Gangwon Province. Analyzing the distribution of HI titer according to the age of the cattle showed the highest BCoV seropositive rate in 5-year-old cattle, and the incidence of cattle with an HI antibody titer of 1:160 or above was 12.1%.