Fasting blood sugar 6.75mmol / L, can not completely exclude diabetes, need to check the postprandial 2 hours of blood glucose and so on. Generally, the normal value of fasting blood glucose <6.1mmol/L, when the value of fasting blood glucose ≥7.0mmol/L or 2 hours after meal blood glucose ≥11.1mmol/L, combined with the typical clinical manifestations of diabetes can be diagnosed with diabetes. Fasting blood glucose 6.75mmol/L is not enough to diagnose diabetes mellitus, because some patients are purely postprandial blood glucose elevation is dominant, so need to review the postprandial 2 hours blood glucose. 1. If the 2-hour postprandial blood glucose is <7.8mmol/L, the fasting blood glucose is impaired and belongs to the pre-diabetes. 2. If 7.8 mmol/L ≤ fasting blood glucose <11.1 mmol/L, then it is impaired glucose tolerance, which is also a pre-diabetic stage. 3. If the fasting blood glucose value is ≥11.1mmol/L, combined with the typical symptoms of diabetes mellitus, i.e., polydipsia, polyphagia, polyuria, and weight loss, then diabetes mellitus can be diagnosed. Fasting blood glucose 6.75mmol/L, it is recommended to go to the hospital in time.