AIM: To study the effects of extract from Ginkgo biloba (Egb) containing 22% flavonoid and 5% terpenoid on chronic liver injury and liver fibrosis of rats induced by carbon tetrachloride (CCl4).METHODS: All rats were randomly divided into control group, CCl4-treated group, colchicine-treated group and Egb-protected group. Chronic liver injury was induced in experimental groups by subcutaneous injection of CCl4and fed with chows premixed with 79.5％ corn powder,20％ lard and 0.5％ cholesterol (v/v). Egb-protected group was treated with Egb (0.5 g/kg body weight per day) for 7 wk. At the end of wk 8, all the rats were killed. Liver function, liver fibrosis, oxidative stress and expression of transforming growth factor β1 (TGF-β1),a-smooth muscle actin (α-SMA) and type Ⅰ collagens in liver were determined. In addition, pathology changes of liver tissue were observed under light microscope.RESULTS: The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and albumin (Aib) in Egb-protected group were notably improved as compared with the CCLL4-treated group (P ＜ 0.01).The contents of serum hyaluronic acid (HA), type Ⅲ procollagen (PCⅢ), type Ⅳ collagen (CIV) and the expression of hepatic tissue TGF-β1, α-SMA and type I collagenin Egb-protected group were significantly lower than those in CCL4-treated groups (P ＜ 0.05, P ＜ 0.01). The degrees of liver fibrosis in Egb-protected groups were lower than those in CCL4-treated groups (6.58 ± 1.25 vs 9.52 ± 2.06, P ＜ 0.05). Compared to the CCL4-treated group, the levels of plasma glutathoine peroxidase (Se-GSH-Px), superoxide dismutase (SOD)and malondialdehyde (MDA) were strikingly improved also in Egb-protected group (P ＜ 0.05, P ＜ 0.01).CONCLUSION: Egb resists oxidative stress and thereby reduces chronic liver injury and liver fibrosis in rats with liver injury induced by CCl4.