The case is a 45-year-old female who underwent right total nephroureterectomy and partial cystectomy for renal pelvic cancer. During the operation, she received blood transfusion. On the 10th postoperative day, she developed high fever and skin rush on the face, which were followed by liver dysfunction and pancytopenia. On the 18th post-operative day, she died of sepsis. Autopsy revealed hypoplasia and aplasia of the bone marrow and severe atrophy of the systemic lymph nodes and spleen. The characteristic clinical course and autopsy findings of this case closely resembled graft-versus-host disease which is observed after bone marrow transplantation or blood transfusion given to patients with severe immunodeficiency. It is therefore strongly suggested that postoperative erythroderma of this case was induced by graft-versus-host reaction due to blood transfusion given during the operation.