Abstract: Enzyme-assisted extraction of polysaccharides from Cordyceps cicadae(CCSP)spores was optimized by response surface methodology. Hepatoprotective effects of CCSP were evaluated by alcohol-induced liver injury model mice. The mice were randomly divided into six groups,including normal group,model group,positive group(silibinin,150 mg/kg)and CCSP groups(50,100 and 200 mg/kg). All the groups of mice were intragastrically administered for 20 days. At the 21st day,all the groups except the normal were intragastrically administered with 12 mL/kg of 50% alcohol every twelve hours for three times. Activities of serum ALT and AST and levels of liver SOD,CAT,GSH-Px and MDA were estimated by reagent kits. The results showed that the optimal enzyme-assisted extraction parameters were indicated as below:Ratio of water to raw material 35 mL/g,cellulase amount 0.64%,enzymolysis pH6.0,enzymolysis time 80 min and enzymolysis temperature 50 ℃. Under this condition,the yield of CCSP was 7.46%±0.12%(n=3). Pre-treatment with CCSP effectively increased the liver index and spleen index in alcohol-treated mice. The elevated serum alanine aminotransferase and aspartate aminotransferase activities of mice after alcohol exposure were inhibited by CCSP administration. Furthermore,pre-treatment with CCSP could efficiently boost the superoxidase dismutase,catalase,and glutathione peroxidase activities,and observably constrain the malondialdehyde level(P<0.05). The findings suggestted that CCSP would be useful for alleviating the alcohol-induced hepatotoxicity via its antioxidant potential.