Human blood pressure is not constant throughout the day. There are two peaks and a trough in blood pressure during the day and night. The human body’s blood pressure rises from 6-9 a.m., forming the first peak, then begins to fall until 4-6 p.m., forming the second peak, and is lowest from zero to two o’clock late at night. There is no fixed time for blood pressure measurement, and it can be done when the body and mood are in a stable state. The best time to measure is within an hour of waking up in the morning or before going to bed at night. When measuring in the morning, it is important to take the measurement within one hour after waking up, after urination and before breakfast. If you are taking antihypertensive medication, take it before you take it. For evening measurements, just do it before going to bed. When measuring blood pressure, you should put your mind at ease, don’t be nervous, and don’t sit down to measure, it is better to sit for 10-20 minutes before measuring.