Objective To observe the effects of erythropoietin-α administered before the total knee arthroplasty (TKA) on the blood transfusion in patients with mild anemia. Methods 60 patients with mild anemia, who were arranged to receive TKA , from 2010-2012 , were assigned to received either 40 000U of erythropoietin-αfor 3 times (once a week) 3 weeks before the surgery (intervention group, n=30) or not (control group, n=30). Then the hemoglobin levels , transfusion ratio , inpatient length of stay and duration of surgery between the 2 groups were analyzed. Results The hemoglobin level was increased from 11.5 g/dL to 14.3 g/dL in intervention group before the surgery (P<0.01). The blood transfusion rate was decreased from 96.6%to 56.6% (P=0.013) during the surgery. And the length of hospital stay was similar between the 2 groups. Conclusion Erythropoietin-αadministered 3 weeks before the TKA surgery could reduce the blood transfusion rate of patients with mild anemia.