Epstein-Barr virus(EBV) has been implicated in the pathogenesis of B-lymphoproliferative disorders, T-cell lymphomas and Hodgkin's disease. In this report, we performed an in situ hybridization study on EBV genome in 10 cases of nasal non-Hodgkin's lymphoma(NHL), 20 cases of Waldeyer's ring(WR) NHL, and 20 cases of nodal NHLs to document EBV association with lymphomas in Koreans. For immunophenotyping, monoclonal antibodies for CD 20, MB 2, CD 45Ro