Inflammatory bowel disease (IBD) is a group of chronic, nonspecific inflammatory disease of the bowel the pathogenesis of which has not yet been clarified, but is generally believed to be related to the interaction of environmental changes, intestinal microecological changes, genetic susceptibility, immune regulation imbalance and other factors. Intestinal microbiota play an important role in physio-logical processes such as nutrient absorption, metabolism and immune response. This article introduces the functions of intestinal microbiota and its significance in the diagnosis and treatment of IBD. 

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