Glycosylated hemoglobin of 12% is generally abnormal, and its normal reference value is usually 4%-6%. Glycated hemoglobin can reflect the average blood glucose level in the last 8-12 weeks. In China, glycated hemoglobin is recommended to be used as an additional diagnostic criterion for diabetes mellitus in medical institutions with standardized testing methods and strict quality control, and the condition for diagnosis is that the glycated hemoglobin is greater than or equal to 6.5%. It should be noted that the measurement of glycosylated hemoglobin is influenced by many factors such as the method of testing, the presence of anemia and hemoglobin abnormalities, and age, and does not reflect instantaneous blood glucose or fluctuations in blood glucose. Glycated hemoglobin is a stable and reliable indicator of the prognosis of diabetes mellitus patients. Therefore, a glycated hemoglobin of 12% is significantly high, and it is recommended that regular hypoglycemic treatment be carried out under the guidance of a professional endocrinologist.