Objective: To observe the clinical effect of Ruangan granule (RGG) in treating liver fibrosis.Methods: One hundred and twenty patients of chronic viral hepatitis B were randomly divided into two groups, 60 patients in the treated group and 60 patients in the control group. They were treated with RGG or composite Biejia Ruangan tablet (复方鳖甲软肝片) respectively for three months. The changes of liver function, liver fibrosis indices, including fibronectin (FN), laminin (LN) and hyaluronic acid (HA), as well as liver morphology by B-ultrasonic examination were observed after treatment. A three-month follow-up study was also conducted. Results: In the treated group, the markedly effective rate was 50.0% and effective rate was 41.7%, while in the control group, the corresponding rates were 26.7% and 55.0% respectively. Comparison of the markedly effective rate between the two groups showed significant difference (P<0.01). The serum levels of FN, LN, HA as well as splenomegaly and portal vein widening in the treated group after treatment were significantly improved (P<0.05), as compared with those in the control group after treatment; significant difference was shown in comparison of serum FN, LN and HA. Conclusion: RGG could improve effectively serum liver fibrosis indices and liver function in patients of chronic hepatitic fibrosis. It is helpful in alleviating and inhibiting the genesis and development of liver fibrosis so as to block the progression of liver cirrhosis.