The recommended time for blood pressure measurement is during the daytime, and the best times are 6:00~10:00, 12:00~13:30 and 16:00-20:00. The circadian rhythm of normal blood pressure is characterized by a double peak and a trough, with a peak at 6-10 a.m. and a peak at 4-8 p.m., and a significant drop in blood pressure at night. Studies have shown that blood pressure fluctuations are related to work and rest time, and that blood pressure is affected by physiological activities and sleep. Only by reducing the blood pressure of hypertensive patients at peak time to the normal range can complications be prevented, but the small peaks and valleys that occur during the lunch break should not be ignored in order to guide the rational use of medication. Therefore, measuring the blood pressure of hypertensive patients at peak times (6:00~10:00, 16:00-20:00) and during lunch break (12:00~13:30) has a positive guiding significance for the treatment and prevention of hypertensive disease. At the same time, because waking the patient up at night will cause the blood pressure that has dropped during sleep to suddenly rise and thus adversely affect the measurement and treatment, nighttime blood pressure measurement is not recommended. In summary, the recommended time for blood pressure measurement is during the daytime, and the optimal time frames are 6:00~10:00, 12:00~13:30 and 16:00-20:00. When abnormal blood pressure occurs, it is necessary to actively consult the doctor and follow the doctor’s instructions for reasonable treatment.