Objective To study the effect and mechanism of Shenshaoruangan Decoction on liver fibrosis in rats.Methods Seventy-two male Wistar rats were selected and normally fed for 1 week.Then they divided into the control group(n=12) and model constructing group(n=60).The model constructing group was subcutaneously and intraperitoneally injected by 40％ CCl4 olive oil for constructing fibrosis rat model.After successfully constructing model,which was divided into the model group(equivalent normal saline gavage),positive control group(colchicines 0.154 mg · kg-1 · d-1),low-dose group(2 mL per 100 g body mass,containing Shenshaoruangan Decoction crude drug 0.23 g/mL),medium-dose group(2 mL per 100 g body mass,containing Shenshaoruangan Decoction crude drug 0.46 g/mL) and high-dose group(100 g/2 mL,containing Shenshaoruangan Decoction crude drug 0.69 g/mL),12 cases in each group.The differences of related indicators rat hepatic fibrosis after 8-weeks treatment were observed.Results The control group was the stage 0 standard,the liver fibrosis degree in the positive control group was significantly better than that in the model group(P＜0.05);the liver fibrosis degree in the low-dose group,medium-dose group and high-dose group was gradually alleviated;the liver fibrosis degree in the high-dose group was significantly slighter than that in the model group and-dose group(P＜0.05).The detection values of PC-Ⅲ,LN,Ⅳ-C and HA in the model group were significantly higher than those in the control group(P＜0.05),and the detection values of PC-Ⅲ,LN,Ⅳ-C and HA in the positive control group,lowdose group,medium-dose group and high-dose group were significantly lower than those in the model group(P＜0.05).Serum SOD detection value of the model group was significantly lower than that in the control group(P＜0.05),the serum MDA level in the model group was significantly higher than that in the control group(P＜0.05);serum SOD level in the positive control group,low dose group,medium-dose group and high-dose group was significantly higher than that in the model group(P＜0.05),while serum MDA level in those group was significantly lower than that in the model group(P＜0.05).Conclusion Shenshaoruangan Decoction can effectively alleviate the liver fibrosis degree,and its mechanism is to reduce the levels of liver fibrosis indicators,inhibit the prodmotion of peroxides and alleviate the damage of free radicals on liver cells.