Abstract: Objective:To study the protective effect of jujube polysaccharides extract on intestinal immune barrier and its mechanism in mice. Methods:70 male ICR mice were randomly divided into 5 groups:negative control group,model group,low(150 mg/kg·bW),medium(300 mg/kg·bW),and high(600 mg/kg·bW)dose group. The mice were gavage continuously for 28 d,and the model was established by intraperitioneal injection of cyclophosphamide on the last day. To study the effects of JPS on the immune organ index,the number of intestinal Peyer’s patches,the intestinal immune-related indicators,the number of intestinal immune cells and the expression of intestinal immune-related proteins in immunosuppressed mice.Results:JPS could protect the normal morphological structure of the intestinal mucosa of mice,increase the index of immune organs and the number of Peyer’s knots in mice,increase the content of IgA and SIgA secreted by the intestine,and enhance intestinal lysozyme and acid phosphatase activity,increases the number of intestinal immune cells and down-regulates the expression of MyD88,NF-κB p65,and IL-1β proteins. Conclusion:Jujube polysaccharide extract has a protective effect on the intestinal immune barrier of immunosuppressed mice,and its mechanism is related to the regulation of MyD88/NF-B pathway related protein expression.