Postprandial blood sugar of 17.0mmol/L is more serious, and patients should go to hospital as soon as possible for relevant examination and treatment to lower blood sugar to a more stable state. Post-meal blood glucose has the most diagnostic value with 2h post-meal blood glucose. Normal people with 2h post-meal blood glucose is less than 7.8mmol/L. If it is a general population found that the post-meal blood glucose is 17.0mmol/L, it can be diagnosed as diabetes. If it is a patient with type I diabetes, the patient drinks more, eats more, loses weight obviously, and the blood sugar continues to rise, without active treatment, diabetic ketoacidosis may also occur, and even coma may occur, which is life-threatening, so the postprandial blood sugar of 17.0mmol/L is more serious, and should be treated by a doctor in time. If type II diabetic patients have postprandial blood glucose 17.0mmol/L, the patients may be combined with myocardial infarction, cerebrovascular lesions, diabetic foot, or lung infection, urinary tract infection, skin infection, etc. Since high blood sugar is a good culture medium for all kinds of microorganisms, infection can aggravate the continuous increase of blood sugar, which will form a vicious circle. Therefore, if a type II diabetic patient has a blood glucose of 17.0 mmol/L after meals, he or she should go to the hospital promptly for ketone body testing, and also test the pH value in the blood to check whether ketoacidosis has occurred. If these conditions occur, treatment such as rehydration, insulin, and correction of hydropower balance should be given immediately to keep the patient out of diabetic ketoacidosis as much as possible.