Abstract: Diabetes mellitus is a chronic metabolic disease caused by many factors. It is one of the major diseases threatening human health in the 21 st century because of high morbidity, morbidity and mortality.Recent studies showed that intestinal flora was closely related to the development and progression of diabetes. Intestinal flora disorder could lead to increased intestinal permeability, systemic inflammation, and oxidative stress response, thereby promoting the formation and development of diabetes.However, probiotics could prevent the occurrence of diabetes by regulating the host intestinal flora, reducing oxidative stress and balancing immune regulation. In this paper, the characteristics of intestinal flora and the interventional effect of probiotics on diabetes mellitus were discussed in this article, in order to provide a reference for diabetes-related research.