The normal value of blood glucose varies according to the different methods of measurement. The methods of blood glucose measurement can be divided into fasting blood glucose, 2-hour postprandial blood glucose and random blood glucose, etc. The normal range of fasting blood glucose is 3.9～6.1mmol/L, the normal value of 2-hour postprandial blood glucose should be less than 7.8mmol/L, and the normal range of random blood glucose should be less than 11.1mmol/L. 1. Adult fasting blood glucose: When determining fasting blood glucose, patients are required to have no energy intake for at least 8 hours, and the normal range of fasting blood glucose for a normal person is 3.9-6.1 mmol/L. 2. 2-hour postprandial blood glucose: the normal value of 2-hour postprandial blood glucose should be less than 7.8mmol/L. 3. Random blood glucose: the normal range of random blood glucose should be less than 11.1mmol/L. If the patient has the typical symptoms of diabetes plus the random blood glucose ≥ 11.1mmol/L, the diagnostic standard of diabetes is reached. If blood glucose abnormality occurs, it is recommended to go to the hospital in time.