To observe the effect of Kangxian Yi-ai formula on HGF and c-Met mRNA in rats with liver precancerous lesions， and thus to investigate its prevention and treatment mechanism. Methods： Seventy-five SD rats were randomly divided into normal group， model group， Kangxian Yi-ai(KXYA) group， Biejiaruangan(BJRG) group and colchicine group. Established the animal models of diethylnitrosamine(DEN)-induced liver precancerous lesions and used KXYA formula to intervene. BJRG tablets and colchicine tablets were taken as control drug. To detect the expression levels of α-SMA in liver by using immunohistochemistry and to detect the expression levels of HGF and c-Met mRNA by using real-time quantitative PCR. Results： The results of immunohistochemistry showed that compared with the model group and the colchicine group， KXYA group could significantly reduce the expression of α-SMA， which is of statistical significance (P<0.01， P<0.05). The results of real-time quantitative PCR showed that compared to the relative expression of HGF mRNA， KXYA group were significantly different with model group and colchicine group(P<0.05). Kangxian Yi-ai formula can significantly increase the expression level of HGF mRNA in rat liver precancerous lesions. The expression of c-Met mRNA were low in each group of DEN-induce liver precancerous lesions， and there is no statistical significance(P>0.05). Conclusion： Kangxian Yi-ai formula can increase the expression of HGF mRNA levels of hepatic lesions in rats， which may be the one of its prevention and treatment mechanism.