Objective: To recombinant the nearly natural human granulocyte-macrophage-colony stimulating factor (GM-CSF) for supplying more safe and steady expressed cytokine in clinic. Method: The eukaryotic recombinant pcDNA3.1-GM-CSF plasmid which was controlled by the CMV promoter was transferred into CHO cell by lipofectamine, selected by G418 and the positive clones was got. The recombinant vector which was rejoined into the groups of DNA of CHO was identified by PCR. Results: The results showed that the protein of rhGM-CSF was about 28 KD by using ELISA, SDS-PAGE and Western blot. Conclusion: rhGM-CSF was expressed steadily and highly. The rhGM-CSF will be of more use value.