The insulin dosage for diabetic patients can be calculated according to body weight. for type 1 diabetic patients, 0.5-1 IU/kg-d. for type 2 diabetic patients, 0.3-0.8 IU/kg-d. To prevent the appearance of hypoglycemia, insulin therapy should be started with a small dose when starting insulin therapy. For obese type 2 diabetic patients with significant insulin resistance, they should receive diabetes education, intensify exercise, and combine oral hypoglycemic drugs to improve insulin sensitivity before starting insulin therapy. Insulin therapy has the highest risk of hypoglycemia of all methods, therefore, drug doses should be developed under the guidance of a physician.