Generally speaking, the difference between high pressure and low pressure is about 30-40 mmHg is the normal range, if the difference is more than 40 mmHg, it means that the pressure difference is large, and it is necessary to adjust the antihypertensive drugs in time, the pressure difference >60 mmHg or the pressure difference <30 mmHg, you should pay close attention to your health condition, and consult a doctor in time if necessary. For normal people, the normal range of blood pressure is high pressure (systolic blood pressure) is 90-140 mmHg, low pressure (diastolic blood pressure is 60-90 mmHg, high pressure and low pressure difference of 30-40 mmHg or so is the normal range, if the difference is not in the normal range, should be concerned about the timely adjustment of antihypertensive medication, if necessary, timely medical treatment. Before measuring blood pressure, you should be quiet, the height of the arm should be the same as the height of the right atrium during the measurement, the measurement of blood pressure may be affected by emotions, weather and other aspects, resulting in fluctuations in blood pressure, it should be measured several times, and it is recommended to take the average of the three measurements as a representative of the blood pressure, to ensure that the measurement of the accuracy.