Abstract: The effect of bariatric and metabolic surgery on obesity with type 2 diabetes mellitus has been widely recognized, so the guidelines for the treatment and management of diabetes mellitus are constantly revised. In order to balance the effect and safety of surgery, innovative surgical methods continue to emerge. But for the effect on diabetes mellitus, high‑level clinical researches are still needed to provide more evidence. For postoperative remission and the mechanism of bariatric and metabolic surgery to alleviate diabetes, and the application of bariatric and metabolic surgery in the treatment of type 1 diabetes mellitus, new researches have emerged constantly. Based on the clinical practices and domestic and foreign literatures, the authors discuss the application of bariatric and metabolic surgery in the treatment of diabetes mellitus.