Objective：To obtain high expression level of HGF protein in vivo by HGF plasmid rapid injection through the tail vein. Methods：Systemic administration of different amount of naked plasmid containing HGF cDNA driven under cytomegalovirus promoter（pCMV-HGF） was injected rapidly into NOD／SCID mice through the tail vein, and the level of HGF protein in the circulation was detected by ELISA. The amount of HGF protein in liver tissue was measured through Western blot. Results：The amount of human HGF protein in the circulation was drastically increased after the injection of the HGF vector, and 20 -滋g／1.6 ml group increased highest. Ｆour hours after the injection of the pCMV-HGF vector, the HGF protein in the circulation of the mice was increased remarkably. Twelve hours later，the concentration of HGF protein reached the maximum that is about 10 ng／ml. Even 6 days after the injection，the HGF protein was still in a high level. The result of Western blot showed that the amount of HGF in liver tissue also increased after injection and reach the peak value at 8 h，and then decreased. Conclusion：Systemic administration of pCMV-HGF via rapid injection through the tail vein can promote high expression of HGF in vivo.