Blood glucose check and monitoring is an important control indicator for diabetic patients, but whether the blood glucose check requires fasting depends mainly on the index and purpose of the check. Routine medical checkups generally check fasting blood sugar, which requires fasting, and requires fasting for more than 8 hours to be completely fasted. If it is to clarify the situation of blood sugar, especially to clarify whether there is diabetes, in addition to checking fasting blood sugar, it is also necessary to check the blood sugar two hours after meals, usually two hours after taking 75g of glucose orally or eating 2 or 2 large buns. For random blood glucose check, it means checking blood glucose at any time and under any circumstances, without necessarily fasting. In addition, for daily monitoring of blood glucose for diabetic patients, besides checking blood glucose before and two hours after three meals a day, it is also necessary to check blood glucose before going to bed and blood glucose at night from time to time, and it is necessary to check at any time when there are uncomfortable symptoms to determine whether there is hypoglycemia, and fasting is not required in this case. Therefore, whether fasting is required for blood glucose check is different according to different situations, fasting is required for fasting blood glucose check, while fasting is not required for two hours after meal blood glucose check and random system.