The 3-hour postprandial blood glucose standard, generally not as a diagnostic criterion for diabetes mellitus, can refer to the random blood glucose standard <11.1mmol/L. Random blood glucose, refers to the blood glucose value of blood drawn at any time of the day. Generally refers to postprandial blood glucose, no need to fast, the results of blood tests at any time. The current diagnostic criteria for diabetes are: 1. Diabetes mellitus is diagnosed when there are typical symptoms, i.e., obvious symptoms such as polyuria, polydipsia, polyphagia, emaciation, etc., and when fasting plasma glucose (overnight glucose without food for 8-10 hours) is greater than 7.0 mmol/L, or when venous plasma glucose of 2 hours of the oral glucose tolerance test is greater than 11.1 mmol/L, or when random blood glucose is greater than 11.1 mmol/L; 2. People without typical symptoms who occasionally measure high blood glucose, if fasting plasma glucose is greater than 7.0 mmol/L, or random plasma glucose is greater than 11.1 mmol/L, it is also necessary to measure plasma glucose again on a non-same day. Diabetes mellitus can also be diagnosed if the diagnostic criteria are met on 2 or more occasions; 3. Glycosylated hemoglobin ≥ 6.5% can be used as a diagnostic criterion for diabetes mellitus depending on the situation. If high blood glucose occurs, you should consult a hospital promptly to determine whether diabetes can be diagnosed after full evaluation by a specialist.