Abstract: Objective:This study explored the protective effect of walnut oligopeptides(WOPs)on alcoholic gastric ulcer and its possible mechanism by establishing a model of acute ethanol-induced gastric ulcer in rats. Methods:Male SD rats were randomly divided into 7 dose groups(n=10):Normal control group,model control group,omeprazole control group(20 mg/kg),WOPs low,medium and high dose groups(220,440,880 mg/kg,respectively). After oral gavage for 30 consecutive days,rats were given 5 mL/kg absolute ethanol to induce gastric ulcer. Then the levels of gastric ulcer index,hematological parameters,prostaglandin E2(PGE2),nitric oxide(NO)and myeloperoxidase(MPO)of gastric tissues in rats were evaluated. Results:The gastric ulcer index of the WOPs low,medium and high dose groups was significantly lower than that of the model control group(P<0.05),and the gastric ulcer index of the WOPs high dose group was lower than that of the omeprazole group(P<0.05). WOPs had a significant inhibitory effect on the abnormal increase of white blood cell count and monocyte percentage in model rats(P<0.05). In addition,WOPs could significantly increase the content of PGE2 and reduce the levels of MPO and NO(P<0.05). Conclusion:The WOPs would have protective effect on alcoholic gastric ulcer,and the probably mechanism of its action was related to reducing the severity of gastric ulcer,increasing the contents of PGE2,reducing the aggregation and infiltration of neutrophils and the pathological increasing of nitric oxide contents.