There is a normal blood glucose regulation mechanism in the human body, and there is a dynamic balance of blood glucose in the human body. If the blood glucose measured at the same point in time is not the same every time, it may be caused by the deviation of the instrument, environmental influence, sterilization error and other reasons. 1. Instrument deviation: different instruments have certain deviation, hospitals use plasma glucose value, while the home version mostly uses whole glucose value, so the measured blood glucose will be different. 2. Environmental influences: Capillary blood glucose examination will be subject to a lot of external environmental interference, such as the depth of the finger is different, different time and so on, the blood glucose are not the same. 3. Disinfection error: iodophor and iodine, which are commonly used in medicine, may lead to elevated blood glucose test results. 75% alcohol can be used to disinfect the blood, and the test can be carried out after drying naturally, and the dilution of the blood by alcohol may also cause certain errors, resulting in different blood glucose results every time. If the difference in blood glucose is not large is normal, it is recommended to go to the hospital for venous blood glucose testing, and compare with the blood glucose test of the glucose meter to ensure the accuracy of blood glucose.