Open heart surgery with non-blood transfusion was performed in 2 cases of severe mitral valve disease with cardiac cachexia by administering recombinant human erythropoietin (EPO). Case 1 was a 72-year-old and case 2 was a 66-year-old woman whose % usual body weight was 71-79% and Ht value on admission was 28.5-30%. Both patients were administered 9000-18000 U/week of EPO and ferrous sulfate pre- and postoperatively. In each case 800-1200 ml of autologous blood was drawn within 3 weeks preoperatively without hemodynamic change or decrease of Ht value. Both patients were received mitral valve replacement with non-blood transfusion. Preoperative administration of EPO and autologous blood preservation allowed open heart surgery with non-blood transfusion even in such a serious case as cardiac cachexia.