It is recommended to measure blood pressure once a day at 6~10 o’clock and once a day at 16~20 o’clock. Blood pressure fluctuates from time to time and is affected by factors such as exertion, emotions, strenuous activities, smoking, medication, and drinking strong tea or coffee. Generally speaking, 6~8 o’clock and 16~18 o’clock are the two peaks of blood pressure in a day. It is recommended to measure blood pressure once in each of these two hours, repeat the measurement after 2 minutes, and take the average value of each measurement three times. This will be relatively accurate. In addition to paying attention to the time period, the measurement of blood pressure, but also pay attention to the measurement of the first half hour should not be strenuous activities, smoking, violent mood swings, etc., empty the bladder, rest for 5 minutes. Take a seated position, with the elbow flush with the heart, and the lower edge of the cuff should be placed about 2.5cm above the elbow for measurement. Correct measurement of blood pressure is essential for the control of blood pressure in hypertensive patients. If there are large fluctuations in self-measurement, immediate medical attention should be sought.