The normal values of pre- and post-prandial blood glucose are different, and there are differences in the normal values of blood glucose in different groups of people, so we should determine whether it is normal according to specific groups of people. First, normal people: normal people without diabetes, fasting blood sugar before meal is 3.9-6.1mmol/L, 2h after meal blood sugar value <7.8mmol/L. Second, pregnant women: during pregnancy, blood sugar control requirements are higher, fasting blood sugar before meal <5.1mmol/L, 1h after meal blood sugar value <10.0mmol/L, 2h after meal blood sugar value <8.5 mmol/L. If one of the above three points is exceeded, gestational diabetes can be diagnosed. Some patients' blood glucose can return to normal after delivery; however, if the blood glucose still exceeds the standard after 6 weeks of delivery, they belong to diabetic patients and should be controlled according to the "five horsemen" of diabetes treatment plan. Diabetic patients: 1, ordinary diabetic patients: younger, less complications, no cardio-cerebral complications, the blood glucose requirements for this part of the patients are more strict, preferably the pre-meal fasting blood glucose control within 6.5-7.3mmol/L, 2h post-meal blood glucose control at 8.0-8.5mmol/L, glycosylated hemoglobin control at 6.2%-6.3% With the gradual increase of age, the complications of diabetes gradually occur, patients may have diabetic retinal disease, cardiovascular and cerebrovascular diseases and diabetic foot. At this time, the requirements for blood glucose control are not very strict, because this part of the patient's motor ability is reduced, can not carry out activities, and consciousness is not very clear, generally require this part of the patient's pre-meal fasting blood glucose in 7-8mmol/L, 2h post-meal blood glucose as long as it does not exceed 10.0mmol/L, glycosylated hemoglobin <6.5%, are considered normal.