Malignant histiocytosis is a rare, usually fatal malignant neoplasm. We present a case of a 62 year-old female with malignant histiocytosis involving the skin, lymph nodes and bone marrow. The patient achieved a complete remission for 1 year after the completion of COPP chemotherapy (cyclophosphamide, vincristine, procarbazine and prednisone). We propose that COPP chemotherapy is a valuable therapeutic regimen for malignant histiocytosis.