The Epstein-Barr virus(EBV), a common herpes virus group, is associated with several disease, such as infectious mononucleosis, Burkitt's lymphoma, Hodgkin's disease, and nasopharyngeal carcinoma. However, many questions remain unknown such as epidemiology and association with disease. In Korea, the epidemiologic data of EBV infection in normal subjects is nearly rare. This study was designed to investigate the rate of EBV infection of normal subjects in Korea. The polymerase chain reaction, more sensitive method than any other for detection of EBV, was used for the detection of EBV. The leukocyte and nasopharyngeal tissue from 35 subjects were examined for the detection of EBV. The EBV was detected in 30 cases(85.7%) fo 35 subjects : 83.3%(5 cases/6cases) in child and 86.2%(25cases/29cases) in adult. EBV was detected 8 cases(22.8%) in leukocyte alone and 7 cases(20.0%) in nasopharyngeal tissue alone. In both leukocyte and nasopharyngeal tissue EBV was detected 15 cases(42.9%). These results suggest that the detection rate of EBV infection of normal children and adults is very high in Korea, and EBV infection begins since early childhood.