Postprandial blood glucose 9.1mmol / L is not necessarily diabetes, may be normal, may also be impaired glucose tolerance, need to distinguish between the blood glucose a few hours after the meal, generally two hours after the meal blood glucose as a diagnostic condition. 1. Normal situation: blood glucose will rise rapidly from half an hour to one hour after meal, and blood glucose can reach the highest value in one hour or so, more than 11.1mmol/L and there are “three more and one less” symptoms when considering diabetes mellitus. Therefore, blood glucose 9.1mmol/L within one hour after meal is normal, not diabetes. 2. Decreased glucose tolerance: the normal value of blood glucose two hours after meal should be <7.8mmol/L. If the value of blood glucose two hours after meal is >11.1mmol/L and there are symptoms of “three more and one less”, it indicates that diabetes mellitus is present. Therefore, at this time, postprandial blood glucose 9.1mmol/L is abnormal, but not diabetes, there may be impaired glucose tolerance, need to improve the fasting blood glucose, OGTT and other related tests. Postprandial blood glucose 9.1mmol/L is recommended to consult a doctor in time.