A 2-hour post-lunch blood glucose of 8.7 mmo/L is on the high side and not normal. The normal value of fasting blood glucose is 3.9~6.1mmo/L, and the normal value of 2-hour postprandial blood glucose is not more than 7.8mmol/L. 2-hour post-lunch blood glucose value of 8.7mmo/L, which is out of the range of the normal value, may be prediabetes, and need to be tested again or improve the oral glucose tolerance test. Fasting blood glucose ≥7.0 mmol/L, or 2-hour post glycemic load blood glucose ≥11.1 mmol/L, or random blood glucose ≥11.1 mmol/L, accompanied by three more and one less symptom (more drinking, more eating, more urination, and weight loss), can be considered to diagnose diabetes mellitus. 2-hour postprandial blood glucose of 8.7 mmo/L is recommended to seek medical attention to improve the examination and treatment under the guidance of the doctor.