Abstract: Objective To explore O-CHCS’s feasibility of being a gene vector for transfecting L929 cells. Methods We constructed plasmid pCMV- hBD2, and the plasmid was introduced into L929 cells by O-CHCS. Total RNA were extracted from the cultured cells, RT-PCR were performed with specific primers for HBD2 and RT-PCR amplification products were identified with agarose gel electrophoresis;the expression of HBD2 protein was verified by Western blot;the antibacterial activity of purpose protein was defected by Kirby-Bauer disk diffusion method, at the same time put the Lipofect as the positive control. Results RT-PCR amplification products by agarose gel electrophoresis were the same size as the target gene by observation; HBD2 gene expression at the protein level was detected by Western blot ；mediums from the cultured cells transfecting with the pCMV-hBD2 could format antibacterial circle against the Staphylococcus aureus, and these results were as same as the Lipofect. Conclusion The eukaryotic expression vector pCMV-hBD2 was successfully constructed and was introduced to the L929 cells, by doing this we verified O-CHCS could be used as a gene vector for HBD2 , and provided a economic and convenient way to artificial synthesis of HBD2.