Since 1972, a unique lymphadenitis called "subacute necrotizing lymphadenitis" has been described in much Japanese literatures and in a few English articles. Although this condition is accepted as a new entity in Japan, it is not yet accepted other countries. Occasionally, we have encountered lymph node biopsies which showed histologic pictures of subacute necrotizing lymphadenitis with clinical impressions of malignant lymphoma. As an initial step to investigating the etiology of this disease, the common clinicopathologic features in 24 cases of subacute necrotizing lymphadenitis were studied. The lesion frequently developed in the cervical lymph node of young women, causing simple enlargement of the lymph node and was accompanied occasionally by fever or pain. The duration of symptoms was within one month and seasonal distribution was not remarkable. In laboratory tests, WBC count was below 4000/mm³ in 8 cases and Widal test was negative in all 4 cases examined. Microscopically, the characteristic finding was the wide area of patch or confluent necrosis associated with numerous karyorrhectic nuclear dust and surrounded by diffuse infiltration of immunoblastic or activated histiocytoid cells. No appreciable increase in plasma cells or neutrophilic infiltration was noted.