Inflammatory bowel disease (IBD) is an autoimmune chronic inflammatory disease of the digestive system, including Crohn disease (CD) and ulcerative colitis (UC). The disease has a worldwide distribution and is also a serious health hazard for our people. In recent years, with the improvement of people’s living standard and the change of diet structure, the incidence of this disease in China is increasing year by year. So far the etiology of these two chronic non-specific intestinal inflammatory diseases is still unclear and may be the result of a combination of environmental, genetic, immune, infectious and psychiatric factors.