Abstract: The largest microbial community of the human microbiome is located in the digestive tract and performs vital functions. The changes in the composition and function of intestinal microflora can influence the occurrence, development and prognosis of intestinal diseases. Diarrhea, irritable bowel syndrome and inflammatory bowel diseases are common intestinal diseases, and the relationship between them and intestinal microflora has attracted more and more attention.

Key words: intestinal microflora, diarrhea, irritable bowel syndrome, inflammatory bowel diseases