Fasting blood glucose 9.0mmol/L is high, once diagnosed with diabetes is the need for treatment. The normal range of fasting blood glucose is generally 3.9~6.1mmol/L, more than 7.0mmol/L has reached the diagnosis of diabetes mellitus, so exclude acute infections, trauma and other factors affecting blood glucose fasting blood glucose 9.0mmol/L high, it is recommended to improve the glucose tolerance test and other tests to determine the existence of diabetes mellitus. Once the diagnosis of diabetes mellitus is confirmed, it is recommended to maintain the blood glucose in a reasonable range through dietary control, appropriate exercise and treatment with glucose-lowering drugs such as insulin and metformin. In case of abnormal blood glucose values, it is recommended to go to the hospital and ask the doctor to make a judgment.