Erythropoietic activity in anemic Plasma of chronic posthemorrhagic anemic men was studied in rats after subcutaneous injection of anemic plasma. Anemic plasma was obtained from blood donors who sold their blood once or twice a week for one or two years to blood bank. Hemoglobin concentrations of 8 blood donors ranged between 4.6 and 8.4 gm/100 ml. Pooled plasma was treated by acidification-boiling method and adjusted to pH 7.5 by adding 0.1 N NaOH. 7ml/kg and 15ml/kg of anemic plasma filtrate was injected to 2 groups of rats respectively for 7 and 8 days. Hemoglobin concentrations, red blood cell counts and reticulocyte counts were observed before and after injection of anemic plasma and no change was induced by the injection. Subsequently, it was concluded that there was no erythropoietin of high titer in the plasma of chronic post-hemorrhagic anemic men.