Erythropoietin (EPO ) is the primary growth factor for the red cell lineage. Recombinant human erythropoietin has been produced by genetic technology since 1985 and since then many clinical trials have repeatedly demonstrated its success in the correction of anamia associated with chronic renal failure, cancer-related anemia, HIV infection, myelodysplasia, reheumatoid arthritis, matermal and neonatal anamia. Other uses of EPO under investigation are in perioperative surgery, autologous blood transfusion, bone marrow transplantation. All of above-mentioned which shown that rHuEPO increases hemoglobin and hematocrit levels and reduces the need for transfusions. Besides, EPO can be used as a marker of fetal anemia and fetal hypoxia. It’s also used to diagnosis of polycythemia vera (PV ) by the serum erythropoietin level and endogenous erythroid colony assay which can distinguished PV relative polycythemia from secondary erythrocytosis. Recent clinical observasions show that EPO even plays a roll in regulation of endocrine abnormal. Up to now, EPO therapy seems to be a safer method for treatment the patients. The side effects included those due to direct administration of EPO and related to increased red cell mass, like flu-like symptoms, hypertensive, iron deficiency, rise in blood viscosity, clotting of dialyzer, hyperkalemia and hyperphosphatemia, which can be prevented by rational use of rHuEPO. Genetic therapy by use EPO-gene transfer is a promising method which will substitude the rHuEPO many times injected.