In normal people, the normal value of blood glucose two hours after meal should be <7.8mmol/L. Under normal circumstances, the corresponding range of blood glucose in fasting is 3.9-6.1mmol/L, 6.1-7.0mmol/L belongs to the impaired fasting glucose; the value of blood glucose two hours after meal should be <7.8mmol/L, 7.8-11.1mmol/L belongs to the impaired glucose tolerance. The 2-hour postprandial blood glucose value is one of the bases for the diagnosis of diabetes mellitus, and the latest criteria for the diagnosis of diabetes mellitus are the typical "three more and one less" symptoms plus the measurement of intravenous plasma glucose at any time of the day ≥11.1mmol/L or fasting blood glucose ≥7.0mmol/L, or the 2-hour blood glucose after the glucose tolerance test (OGTT) ≥11.1 mmol/L, or glycated hemoglobin ≥6.5%, and one of these four matches is diagnostic of diabetes mellitus. When there is an abnormality of 2-hour blood glucose after meal, you should go to the hospital in time, under the guidance of the doctor for further examination, to clarify the cause of the disease and then carry out appropriate treatment. If you are not feeling well, consult a doctor promptly.