OBJECTIVE： To study the preventive effect and mechanism of Wei medicine Kunlun snow chrysanthemum polysaccharides （KSCP） on carbon tetrachloride （CCl4）-induced acute liver injury in mice. METHODS： 96 mice were randomly divided into normal group （normal saline）， model group （normal saline）， Biphenyl diester dropping pill （positive control， 1.5 mg/10 g） and KSCP low-dose， medium-dose， high-dose groups （0.3， 0.6， 1.2 mg/10 g）， 16 in each group， with intragastric administration， once a day， for 10 d. Except for normal group， mice in other groups were intraperitoneally injected 1％CCl4 rapeseed oil solution to induce liver injury. After 24 h of modeling， the levels of alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， tumor necrosis factor α （TNF-α）， interleukin 1 （IL-1） in serum， levels of malondialdehyde （MDA）， superoxide dismutase （SOD） in liver tissue were detected； the liver， spleen indexes were calculated. Pathological changes of liver tissue were observed， pathological scoring was conducted. The protein expressions of apoptosis-related genes Caspase-3， Bcl-2， Bax in liver tissue were detected. RESULTS： Compared with normal group， levels of ALT， AST， TNF-α， IL-1 in serum， MDA level in liver tissue and liver， spleen indexes in model group were obviously increased （P＜0.01）； SOD level in liver tissue was decreased （P＜0.01）； pathological changes in hepatocellular necrosis， degeneration and inflammatory cell infiltration， and pathological score in model group was obviously increased （P＜0.01）； caspase-3 protein expression and Bcl-2/Bax ratio in liver tissue in model group were obviously decreased （P＜0.01）. Compared with model group， above-mentioned indexes in each administration group were obviously improved （P＜0.05 or P＜0.01）. CONCLUSIONS： KSCP has certain preventive effect on CCl4-induced acute liver injury in mice， and its mechanism may be associated with anti-oxidation， anti-inflammation and regulation of apoptosis-related protein expressions.