A 14 7/12-year-old boy with acute myeloblastic leukemia M3v was admitted with disseminated intravascular coagulation, otitis media, lobar pneumonia, and splenomegaly. After induction therapy, M2 bone marrow was attained but splenomegaly persisted. Abdominal ultrasonography, which revealed diffuse splenomegaly at admission, showed splenic nodular lesions at the end of the induction therapy. The lesions persisted after M1 bone marrow was attained. He developed acute appendicitis and was operated. Ultrasonography-guided aspiration biopsy revealed nonspecific purulent abscess. Gram's stain and aerobic culture revealed no microorganism or fungi. Splenectomy was performed. The pathologic examination confirmed the diagnosis. He did not have an appropriate bone marrow donor, and developed bone marrow relapse and died.