The latest survey data shows that the prevalence of diabetes among adults in China is about 11.6%, with a total of more than 110 million, of which type 2 diabetes accounts for 90%, causing a great burden to families and society. The traditional treatment of diabetes includes diet control, diabetes education, exercise, blood glucose monitoring, and medication, commonly known as the “five carriages”, but these treatments can hardly cure diabetes fundamentally, keep the patient’s blood glucose stable for a long time, or prevent the occurrence and development of various complications of diabetes fundamentally. Strict dietary control and repeated fluctuations in blood glucose levels cause constant mental stress to patients and affect quality of life. In the 1990s, Pories et al, a surgeon at the University of North Carolina, discovered by chance that patients with combined type 2 diabetes who underwent weight loss surgery for the surgical treatment of morbid obesity lost significant weight while their blood glucose rapidly returned to normal and no longer required any glucose-lowering measures for maintenance, thus creating a new avenue for surgical treatment of type 2 diabetes. A Meta-analysis by Buchwald et al. of 135,246 patients in 621 publications from 1990 to 2006 showed a significant reduction in body mass and good results in the treatment of co-morbidities in obese patients after surgery, with 78.1% of T2DM completely cured and 86.6% significantly improved. Surgical treatment of type 2 diabetes is highly effective and is regarded as the “sixth carriage” of diabetes treatment. These surgical procedures reduce the intake and absorption of food and change the secretion of hormones in the intestine-insulin axis through the reconstruction of the digestive tract, which effectively reduces the patient’s weight and improves insulin resistance, thus correcting the disorder of blood glucose metabolism. The patient’s blood glucose and glycated hemoglobin are controlled at normal levels, freeing him from the dependence on drugs and exogenous insulin. The diabetes is in clinical remission or even complete clinical remission. Laparoscopic surgery is popular among patients and doctors because of its many advantages such as less trauma, faster recovery, fewer complications, less patient pain and shorter hospital stay. The incidence of surgical complications (anastomotic leak, bleeding, incisional infection, pulmonary embolism, etc.) in diabetes mellitus is about 5%, and distant complications may include dumping syndrome, anastomotic stenosis, marginal ulceration, closure line dehiscence, and internal hernia. Nutritional deficiencies associated with reduced gastric volume are mainly impaired absorption of Vit B12 and iron. Reduced secretion of internal factors directly affects the binding and absorption of Vit B12, and reduced secretion of gastric acid affects the absorption of iron, so patients need to supplement Vit B12, iron, and also Vit B complex, folic acid, and calcium as needed after surgery.