Generally, the normal value of 1-hour postprandial blood glucose is 6.7-9.4 mmol/L, the normal value of 2-hour postprandial blood glucose is less than 7.8 mmol/L, and the normal value of 3-hour postprandial blood glucose is 3.9-6.1 mmol/L. Postprandial blood glucose is mostly 1-hour postprandial blood glucose, 2-hour postprandial blood glucose and 3-hour postprandial blood glucose. Clinically, 2-hour postprandial blood glucose is usually used as a reference, and the normal value of 2-hour postprandial blood glucose should be less than 7.8mmol/L. Measuring postprandial blood glucose helps to diagnose diabetes. If the 2-hour postprandial blood glucose value is between 7.8 and 11.1 mmol/L, it belongs to abnormal glucose tolerance, i.e., the stage of impaired glucose regulation, and is considered as prediabetes. If the 2-hour postprandial blood glucose value is ≥11.1 mmol/L with typical symptoms of diabetes, diabetes is usually diagnosed. If the postprandial blood glucose monitoring exceeds the normal value, you should go to the hospital as soon as possible for relevant examinations, so as to achieve early detection, early prevention and early treatment.