The ideal blood glucose control should be all-weather, including fasting, post-meal, activity, work and sleep periods. Because measuring blood sugar at a certain time alone can only reflect the blood sugar level at that moment of detection, but cannot represent the blood sugar level at other times, and blood sugar is not constant and fluctuates. However, it is not possible to measure blood glucose at any time and anywhere every day. Nowadays, the customary practice is to conduct a more comprehensive blood glucose test at intervals (such as about half a month) as a basis for guiding treatment and judging the effect of treatment. The testing requirements are: once before 3 meals (fasting), once 2 hours after 3 meals (counting from the first bite), and 6 times throughout the day (if necessary, one more time before bedtime). The test results were determined as follows: ideal blood glucose level before meal 4.0-7.0mmol/L, acceptable level 7.0-10.0mmol/L, unacceptable level more than 10.0mmol/L; blood glucose 2 hours after meal and before bedtime. Ideal level 4.0–10.0mmol/L, acceptable level 10.0–12.0/L, unacceptable level greater than 12.0mmol/L. Glucose users should adjust their treatment according to the above indicators. When should blood glucose testing be performed? How often is it appropriate to test blood glucose at intervals? For this question, it must depend on the specific condition of the individual. Generally speaking, blood glucose testing can be divided into fasting blood glucose, pre-meal blood glucose, 2-hour post-meal blood glucose and random blood glucose depending on the time, and the blood glucose detected at different times has different clinical significance.