OBJECTIVE：To s tudy improvement effect and mech anism of ilicifoliosids alkaloid A （HBOA）on non-alcoholic fatty liver disease in rats. METHODS ：SD rats were randomly divided into blank control group ，model group ，Silybin capsule group（positive control ，26.25 mg/kg），HBOA high-dose ，medium-dose and low-dose groups （100，50，25 mg/kg），with 10 rats in each group. Except that blank control group fed normal feed ，the other groups were continuously fed with high-fat diet for 8 weeks to induce non-alcoholic fatty liver disease model. Form the 9th week ，blank control group and model group were given constant volume of 0.6％ CMC-Na solution ，and administration groups were given corresponding drugs by intragastric admini- stration，once a day ，for consecutive 4 weeks. The general information of rats were observed and the body weight increase ，organ （liver，kidney and spleen ）indexes were calculated ；the contents of AST ，ALT，TC，TG and NEFA in liver tissue were detected ， and SOD，GSH-Px activities and MDA content in the serum were also determined. The protein expression of PPARα in liver tissue was detected by immunohistochemistry. RESULTS ：Compared with blank control group ，the body mass increase and liver index of rats in model group were increased significantly （P＜0.01）；fat deposition could be observed in the liver ；the activities of SOD and GSH-Px in serum were reduced significantly ，and the contents of MDA ，the contents of AST ，ALT，TC，TG and NEFA in liver tissue were significantly increased ，and the protein expression of PPARα was decreased significantly（P＜0.01）. Compared with model group ，the body mass increase and liver index of the rats were decreased significantly in administration groups （P＜0.05 or P＜0.01），liver fat deposition was improved ，the activity of SOD and GSH-Px in serum （except for HBOA low-dose group ）were increased significantly while MDA content ，the contents of AST ，ALT，TC（except for HBOA low-dose group ），TG（except for HBOA low-dose group ） and NEFA in liver tissue were decreased significantl y，while protein expression of PPAR α 15177460685@163.com was increased significantly （P＜0.05 or P＜0.01）. Some of the above indexes of HBOA high-dose group were 电话：0771-5302433。E-mail：junlin898@126.com significantly better than HBOA medium- and low-dose group（P＜0.05）. CONCLUSIONS ：HBOA has a certain improvement effect on non-alcoholic fatty liver disease in rats caused by high-fat diet ，and its mechanism may be related to improving lipid metabolism disorders ，anti-oxidative stress and up-regulating the expression of PPARα.