Six hundred and eight-four cases with non-Hodgkin's lymphomas (NHL) in Osaka, Japan were reviewed, using current histopathological classification to obtain a general feature of Japanese lymphomas. There were no remarkable differences in the distribution of age, sex and the location of primary tumors between Japanese NHL and the disease in Western races. Histologically, however, several differences were present; in particular, the lower frequencies of nodular lymphomas of nodal origin and lymphocytic type of nodal and extranodal origin in the present cases. About 10% of the cases show a peculiar histology characteristic for adult T cell lymphomas. From this study, it appears that the ratio of low-grade malignant NHL in Japan is much lower than in the Western countries.