Fasting fingertip blood glucose of 6.3 mmol per liter is slightly higher than the normal level, which is usually not very dangerous, but whether it is diabetes or not needs to be further examined under the guidance of a doctor. Normal fasting blood glucose is 3.9 to 6.1 mmol per liter, higher than or equal to 7.0 mmol per liter and the patient appears to have three more and one less symptoms, such as drinking more, urinating more, eating more and losing weight. Laboratory tests and pancreatic beta cell function tests can be performed to confirm the diagnosis of diabetes mellitus. Blood glucose examination includes fasting blood glucose and postprandial blood glucose, fasting blood glucose before the need for patients to fast for 8 to 12 hours, after the examination can drink 75 grams of glucose, and then an interval of 2 hours to measure the postprandial blood glucose, when the fasting blood glucose is greater than or equal to 7.0 millimoles per liter, two hours after the meal blood glucose is greater than or equal to 11.1 millimoles per liter and there are typical symptoms, can be diagnosed as diabetes mellitus. If the patient’s fasting fingertip blood glucose is 6.3 mmol per liter and wants to determine whether he or she is diabetic, he or she needs to go to the hospital and be judged by a professional doctor.