The acute toxicity of rHu-EPO, newly developed recombinant erythropoietin, was tested in beagle dogs. rHu-EPO, when administered intravenously at 25, 000 IU/kg, did not cause any death. Also, rHu-EPO did not induce any change of body weight, food intake and clinical signs compared to controls. There were no significant changes in hematological, urine analysis and pathological examination. These results showed that rHu-EPO did not induce any remarkable toxic response and the $LD_50$ was greater than 25, 000 IU/kg in beagle dogs.