Delayed drop of blood glucose after meal may be due to impaired glucose tolerance or diabetes mellitus. It is recommended to consult a doctor in time to improve relevant examinations such as glucose tolerance test, insulin and C-peptide release test, to fully assess the condition, adjust diet, exercise appropriately, and apply hypoglycemic drugs or insulin under the guidance of the doctor. After eating, insulin secretion increases to maintain normal blood glucose level. Delayed drop of blood glucose after meal suggests that there may be abnormal insulin secretion or insulin resistance. Fasting blood glucose, glycosylated hemoglobin, glucose tolerance test, insulin and C-peptide release test and other related tests should be perfected to make a clear diagnosis, and there is a possibility of impaired glucose tolerance or diabetes mellitus. Abnormal glucose tolerance belongs to pre-diabetes, through diet therapy, exercise therapy, medication and other comprehensive treatment means, it is possible to return to normal. After diagnosis of diabetes mellitus, long-term glucose control treatment should be carried out to maintain blood glucose within the target range and monitor the fluctuation of blood glucose at regular intervals. Those with delayed postprandial blood glucose drop should go to the hospital and be treated under the guidance of a doctor.