The starting dosage of insulin in diabetic patients should be determined according to the patient’s duration of diabetes, type of diabetes, whether or not to combine oral hypoglycemic drugs, blood glucose level and so on. 1. Type 1 diabetes mellitus: T1DM whose body weight is within plus or minus 20% of the adult ideal body weight, if there is no special circumstance, the total daily insulin requirement is 0.4~0.8 U/kg, and the total daily amount can be started with the minimum dosage of 12~18 U. Children should be handled as appropriate according to their age, body weight, and glucose situation. 2. Type 2 diabetes mellitus: the starting dose of basal insulin can be calculated according to body weight, usually 0.1~0.3U/(kg-d); for HbA1c＞8.0%, it can be considered to start at 0.2~0.3U/(kg-d); those with BMI≥25 kg/m² can be considered to start at 0.3U/(kg-d). When blood glucose abnormalities occur, it is necessary to actively consult the doctor and follow the doctor’s instructions for rational treatment.