Glycated hemoglobin of 13.8% is on the high side, and diabetes can be diagnosed if the symptoms of diabetes “three more and one less” are present at the same time. Glycated hemoglobin is formed by combining hemoglobin and glucose in red blood cells. Because the half-life of red blood cells is 120 days on average, its value can reflect the average level of blood glucose of the human body in the past 8 to 12 weeks, which is closely related to the patient’s blood glucose concentration and the control of the disease, and its normal value is 4.0% to 6.0%. Glycated hemoglobin 13.8% is significantly higher than the normal value. If the fasting blood glucose is more than 7.0mmol/L, or the two-hour postprandial blood glucose is more than 11.1mmol/L, or the random blood glucose is more than 11.1mmol/L, or the glycosylated hemoglobin is ≥6.5%, and at the same time there are the “three more and one less” diabetes symptoms, then diabetes can be diagnosed. Glycosylated hemoglobin 13.8% should be timely consultation, improve the fasting blood glucose, postprandial blood glucose and other related examinations, standardized treatment.