Gastric diversion surgery was first used for weight loss, but in the early 1980s, the medical community accidentally discovered that a type of surgery for weight loss could “incidentally” cure type 2 diabetes. After continuous clinical practice, doctors found that the procedure was an effective treatment for diabetes. Thus, gastric diversion surgery is a new boon for diabetic patients. Type 2 diabetes accounts for 85-90% of the total number of diabetes, and the prevalence is increasing year by year, with more than 200 million patients worldwide, and its complications cause high death and disability rates, seriously threatening the health and lives of patients. However, all of the above-mentioned medical treatments cannot ensure that the patient’s blood sugar returns to normal level and cannot prevent the emergence and further aggravation of various diabetic complications. In this regard, gastric diversion surgery has opened up a new path for diabetes treatment. A comprehensive analysis of 22,094 patients showed that 84% of type 2 diabetes was completely reversed after gastric diversion surgery, and most patients stopped taking oral medications or insulin therapy before discharge from the hospital. Gastric diversion surgery is suitable for the treatment of any type of diabetes, but only differentiates in terms of therapeutic efficacy. After a comprehensive survey, it was found that gastric diversion surgery is 100% effective in curing type 2 diabetes and has very good results in treating type 1 diabetes.