Three patients with plasma cell leukemia are reported. Two of them had a previous history of myeloma; the third one started with a plasma cell leukemia. Diagnosis was made from the required presence of 20% plasma cells in the peripheral blood. In all 3 cases, bone marrow aspiration and peripheral blood showed plasma cells strongly positive for acid phosphatase and alpha-naphthyl acetate esterase, and negative for periodic acid-Schiff. The first patient was treated with a polychemotherapy regimen that included vincristine, cyclophosphamide, chlorambucil and prednisone, and the second patient with melphalan and prednisone; the third one, who started with plasma cell leukemia, received total body irradiation at the dose of 600 rad. The results of the therapy and survival time, which was never more than 3 months, are in accord with other reports in the literature.