Although surgical treatment of diabetes (metabolic surgery) has been gradually promoted and popularized, it is regrettable to tell you that not all patients can be treated with surgery, and only a small proportion of obese type 2 diabetic patients are eligible for surgical treatment if they are screened at all levels. Especially with the deepening of our research on surgery, the issue of indications for surgery has been constantly updated and improved. Combining my clinical experience over the years, I have summarized the scope of indications as follows: patient’s age ≤ 65 years; patient’s T2DM duration ≤ 15 years; patient’s pancreatic islet reserve function is more than 1/2 of the lower limit of normal, and C peptide ≥ 1/2 of the lower limit of normal; patient’s T2DM type 2 diabetes mellitus is accompanied by high level of obesity with BMI>=35kg/m2, preferred surgical treatment; patient’s BMI>=27kg/m2, drug treatment, preferred surgical treatment; and patient’s BMI>=35kg/m2, preferred surgical treatment. Surgery is preferred for patients with T2DM type 2 diabetes with high obesity and BMI>=35kg/m2; surgery is preferred for patients with BMI>=27kg/m2 who are not satisfied with medication; surgery is an option for patients with waist circumference >90cm in men and >80cm in women; surgery is not recommended for patients who have been blinded, have significant renal damage, or have a history of myocardial infarction or stroke; patients do not have serious mental disorder or mental retardation; the patient is fully aware of surgical procedures for the treatment of diabetes mellitus, and is willing to understand the potential complication risks of surgery. The patient fully understands the risk of potential complications of surgery, and understands the importance of postoperative changes in diet and lifestyle and is willing to bear them; the patient’s ability to actively cooperate with the postoperative follow-up is also a consideration in the selection of surgery. Waist circumference, in particular, was previously not part of the surgical evaluation, but patients with abdominal obesity combined with diabetes have benefited even more than normal obese patients from this surgery. This alone will help more diabetics to have a healthy body sooner. In conclusion, diabetic patients who want to have this surgery must undergo a pre-operative examination and evaluation to make sure that they can do it before they can make the next step in their surgical plan.