Gastric Bypass, also known as Roux-en-Y short-circuit gastrointestinal surgery, Roux-en-Y gastrointestinal bypass surgery, and gastrointestinal bypass surgery, is one of the commonly used procedures for weight loss, and restricting intake while reducing absorption is its main mechanism. It is currently the gold standard procedure for the surgical treatment of obesity in the United States. Gastric bypass surgery was first proposed by Mason et al. in 1967 for the treatment of obesity, and was first reported by Wittgrove et al. in 1994 using laparoscopic techniques for gastric bypass surgery. In clinical practice, it was found that obese patients with type 2 diabetes showed improvement in both obesity and diabetes symptoms after gastric diversion surgery, an unexpected finding that made surgical treatment of diabetes possible. Further research showed that the surgery changed the physiological flow of food through partial gastric block, gastrointestinal anastomosis and enteroenteric anastomosis, which eliminated insulin resistance in the patient’s body, and promoted insulin secretion in the patient’s body by changing intestinal neuroendocrine, reducing islet cell apoptosis, and restoring islet function, thus achieving the purpose of treating diabetes. After nearly 20 years of research and practice in the global field of diabetes medicine, gastric diversion surgery has developed into a mature diabetes treatment method, and is also the only method that can achieve a clinical cure for type 2 diabetes. In the United States, in January 2009, the American Diabetes Association (ADA), the world’s leading authority on diabetes treatment, officially included gastric diversion surgery in the Diabetes Prevention and Control Guidelines, establishing it as a routine treatment for diabetes. In China, the Chinese Medical Association, the Chinese Medical Association, the Chinese Medical Continuing Education Center and other authoritative institutions have made gastric diversion surgery a key promotion project for three consecutive years.