Background The probability and risk of operations increase in patients with type 2 diabetes mellitus.For diabetic patients,blood glucose control is a key factor to improving the prognosis of surgery.During perioperative period,insulin therapy is usually advised to be used for surgical patients with type 2 diabetes.However,the insulin regimen which one is better remains controversial.In this study,we estimated the efficacy,safety and advantage of different insulin therapy strategy during perioperative period.Methods A total of 1086 cases of surgical patients with type 2 diabetes mellitus enrolled in the present study.According to the glucose level at admission,all patients were divided into relatively high glucose group (group A,fasting blood glucose (FBG) ＜13.9 mmol/L) and higher glucose group (group B,FBG ＞13.9 mmol/L).Patients in group A randomly accepted premixed insulin twice a day,or basal insulin plus oral medications,and were divided into group A1 and A2 respectively.Patients in group B randomly received premixed insulin twice daily,basal insulin plus oral hypoglycemic agents,or basal insulin plus preprandial insulin,and were divided into group B1,B2 and B3 respectively.The data of the preoperative preparation time,the daily doses of insulin used in different periods,postoperative incision healed installments,hypoglycemic events,the total hospitalization time,postoperative complications were all collected and statistically analyzed.Results Compared the main outcome measures in groups treated by premixed insulin therapy,both in preoperative preparation and postoperative period,the daily insulin dosage and the frequency of hypoglycemic events were decreased in groups treated by basal insulin therapy (P ＜0.05).The preoperative preparation time and the total hospitalization time in groups with basal insulin therapy were shorter than that in groups with premixed insulin therapy (P ＜0.05).The incision healing rate of stage Ⅰ,Ⅱ and Ⅲ among different therapy protocols were significantly different (P ＜0.05).Conclusions Basal insulin therapy could be used in diabetic patients undergoing elective major and medium surgery during whole perioperative period.Basal insulin therapy strategy,including a single injection of basal insulin and basal insulin plus preprandial insulin injection subcutaneously,is superior to premixed insulin therapy in the perioperative blood glucose management,and it could be viewed as the best choice in glucose control during perioperative period.