Gastric diversion surgery is effective in treating diabetes and is significantly better than medical treatment. But even so, not any patient can be treated with this procedure. That is, there are conditions that must be met in order to have this surgery. So, what are the conditions that need to be met for surgery to treat diabetes? 1, meet the diagnostic criteria of type 2 diabetes; 2, islet function is in the compensatory phase (plasma insulin level > normal value); 3, the history of diabetes does not exceed fifteen years, the islet still has some function, more than fifteen years islet function is very poor, then the effect of surgery is poor, often can not completely stop insulin after surgery; 4, no serious complications; 5, the history of diabetes is less than 15 years or age is less than 70 years . 6, type 2 diabetes with high obesity, BMI>=35kg/m2, surgery is preferred; BMI>=28kg/m2, unsatisfactory drug treatment can choose surgery. However, surgery should not be the last treatment choice for diabetic patients, but should be considered as one of the treatment choices in the earlier stages of obese diabetes treatment. Of course, these alone are still not the final determination of whether the surgery can be done, but also to undergo a strict pre-operative examination and evaluation in the hospital to discover the risk factors for the surgery and to ensure the surgical results. If it is determined that the surgery can be done without problems, the doctor will only give arrangements to develop the next step of the surgical plan.