To reduce the amount of homologous blood transfusion, recombinant human erythropoietin (rHuEPO) administration or preoperative autologous blood donation were performed in 42 patients who underwent elective heart surgery. rHuEPO was administrated intravenously every two days from the 14th preoperative day to the 14th postoperative day (Group E; 19 cases). Preoperative autologous blood donation was done from the 14th day prior to operation once or twice (Group S; 13 cases). There were another 10 cases who did not receive rHuEPO administration or make preoperative blood donations (Group C). In every case, autologous blood donation was performed during preparation for cardiopulmonary bypass at operation. No homologous blood transfusion was done in 14 cases of Group E (74%), 11 cases of Group S (85%), and 6 cases of Group C (60%). Of the 11 patients who required homologous blood transfusion, one was elderly (>65y. o.), 3 had prolonged cardiopulmonary bypass (>3hr), 3 had low body weight (<45kg), 1 had anemia at administration with a red blood cell count of <3.5×10⁶/mm³, and 2 cases had large blood loss during operation (>1, 200ml).