OBJECTIVE： To screen the active part of Saccharum officinarum leaves against liver injury. METHODS： The S. officinarum leaves were extracted with 80％ ethanol to obtain ethanol extract， after dispersed with water， ethanol extract was respectively extracted with petroleum ether， ethyl acetate and n-butanol to obtain corresponding polar parts. The residual part was water part. Totally 108 mice were randomly divided into blank group A （0.5％ CMC-Na and 3.5％ polysorbate 80 solution）， blank group B （purified water）， model group （purified water）， biphenyl diester group （positive control， 0.2 g/kg）， S. officinarum leaves ethanol extract group， different polar parts of S. officinarum leaves group （petroleum ether， ethyl acetate， n-butanol， water， 22.92 g/kg crude drug， 0.5％ CMC-Na and 3.5％ polysorbate 80 solution as solvent）， with 12 mice in each group. They were given relevant medicine intragastrically once a day， for consecutive 12 d. 1 h after last medication， except for blank group A and blank group B， mice in other groups were given 0.15％ CCl4 peanut oil （0.1 mL/10 g） solution to induce acute liver injury model. 16 h later， general information of mice was observed， and the serum contents of ALT and AST were determined. The liver histopathological changes were observed and the Ishak scores were scored. RESULTS： Compared with blank group B， each index of blank group A had no significant difference （P＞0.05）. Compared with blank group A， model group had sparse hair and slow movement， and was emaciated. Serum contents of ALT and AST were increased significantly （P＜0.01）. The structure of hepatic lobule was severely damaged； the structure of hepatic cord and sinus was not clear； the arrangement of hepatic cord was disordered， and the Ishak score was significantly increased （P＜0.01）. Compared with model group， general information of mice was improved in administration groups. Serum contents of ALT and AST were decreased in biphenyl diester group， S. officinarum leaf ethanol extract group and S. officinarum leaf ethyl acetate group （P＜0.05 or P＜0.01）. The pathological damage of liver tissue was significantly relieved， and Ishak score was significantly reduced （P＜0.05 or P＜0.01）. CONCLUSIONS： The ethyl acetate part of ethanol extract from S. officinarum leaves is active part against CCl4-induced acute liver injury of mice.