Fasting blood glucose 6.3mmol/L is slightly higher than normal and may return to normal after standardized diagnosis and treatment. The normal value of fasting blood glucose is between 3.9-6.1mmol/L. Therefore, fasting blood glucose 6.3mmol/L is slightly higher than normal, which may be caused by infections, stress and other reasons for high blood glucose, or pre-diabetes, which needs to be clearly diagnosed and treated under the guidance of specialized doctors. If high blood glucose is caused by infection or stress, the blood glucose level can be normalized after controlling the infection and relieving the stress factors as prescribed by the doctor; if it is pre-diabetes, the blood glucose level can be controlled in the normal range by controlling the diet and actively exercising; if the effect of the diet and exercise is not good, the blood glucose level can be treated with medication as prescribed by the doctor. If you find that your blood glucose level is elevated, you should consult a doctor in a timely manner to clarify your condition, so as to avoid any delay in treatment.