Hantaviruses belong to the genus Hantavints and Hantaan, Seoul, Puumala, Belgrade and Sin Nombre viruses are the etiolgic agents of two serious hantaviral diseases of humans. The rodent hosts and the specific etiologic agents of haemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS) are known and many reported cases occUlTed in Eurasia and Americas. Wild rodents trapped in 13 different areas of Korea from 1994 to 1998 were investigated against hantavirus infection. A total of 718 wild rodents and 10 species were trapped and found 630 (87.7%) of them were Apodemus agrarius. Indirect immunofluorescent antibody technique (IFAT) was performed for hantaviruses infections using different hantavirus antigens. Hantavirus antibodies were found in 68 (10.8%) out of 630 A. agrarius, 8 (42.1%) of 19 Rattus norvegicus. Among 68 lungs and other tissues of antibody positive A. agrarius, 5 (7.4%) were antigen positive. IFA titers of 5 positive A. agrarius sera showed higher titers against Puumala or Sin Nombre viruses than Hantaan virus. These results suggest that there may be are possibilities of existence of a noble hantavirus in Korean wild rodents.