Gastric bypass surgery is now a common surgical procedure for the treatment of diabetes. According to statistics, most patients who are eligible for the procedure are able to get rid of their dependence on medications after the surgery and can keep their blood sugar within a healthy range by simply exercising appropriately and eating well, which significantly improves the quality of life of diabetic patients. Unlike traditional medication, gastric bypass surgery is performed by modifying the gastrointestinal tract so that the blood glucose drops to a level that the body can control itself, with the most intuitive changes being weight and diet. Many people suffer from diabetes because long-term obesity leads to high insulin resistance, and the pancreas is overloaded for a long time before its function is impaired, so weight loss is also an effective means of treating obese diabetes. Gastric bypass surgery allows patients to lose a large amount of excess weight in a short period of time, which greatly reduces insulin resistance and naturally makes their own insulin control of blood glucose stronger. At the same time, gastric bypass surgery also reduces the patient’s ability to eat and absorb. Compared to people who have not had surgery, patients who have had weight loss metabolic surgery surgery will have less blood sugar rise after eating and less pressure to regulate. In addition, the surgery also changes the intestinal flora division and hormone secretion, which also have a certain effect on lowering blood sugar, and these changes work together to give patients the ability to regulate their blood sugar on their own again. However, gastric bypass surgery does not completely restore the function of the pancreas, and high blood glucose cannot be completely reduced to a healthy range. Patients should also develop the habit of exercise to enhance the vitality of the pancreas for better results of the surgery.