This study was performed to determine the toxic effect of DA-3030(granulocyte-colony stimulating factor, G-CSF) in beagle dogs. DA-3030(G-CSF) was injected intravenously at doses of 115 $mu extrm{g}$/kg/day, 11.5 $mu extrm{g}$/kg/day and 1.15 $mu extrm{g}$/kg/day seven days per week for 28 days. After completion of the treatments, the dog were necropsied. The number of dead animal was zero in all groups. No specific clinical sign was found, either. In hematological results, WBC was significantly increased dose-dependently in treated groups. In histopathological findings, megakaryocyte and rubricyte were found in the liver and spleen at the dose of 115 $mu extrm{g}$/kg/day. Therefore, we could find the extramedullary hematopoiesis was increased. Megaka yocyte and rubricyte were increased in bone marrow, too. In conclusion, those signs were estimated the pharmacological effect of DA-3030(G-CSF). According to the results, non toxic dose of DA-3030(G-CSF) was higher than 115 $mu extrm{g}$/kg/day.