Abstract: There is a variety of gut microbiota in human body, which is closely associated with the health and disease. Normal gut microbiota can produce colonization resistance to pathogens. Antibiotics can affect the composition of gut microbiota and change the intestinal microenvironment, resulting in intestinal microecological disorders, which in turn cause intestinal pathogenic infections and other diseases. In this paper, the concept of intestinal microecology, the mechanism of intestinal colonization resistance, the effect of antibiotics on intestinal microecology, and the treatment methods were reviewed, aiming to provide the information for the rational use of antibiotics and the development of more effective treatment methods to maintain the stability of intestinal microecology.