The differential blood pressure refers to the difference between systolic and diastolic blood pressure, which should be in the range of 30mmHg-40mmHg in most normal people. If the differential blood pressure is too large, it often indicates atherosclerosis, mainly because the diastolic pressure is too low, resulting in a large differential pressure, and some people will even exceed 70mmHg, 80mmHg, generally seen in the middle-aged and elderly, especially the elderly. If the differential pressure is too low, for example, 20 mmHg, this is often seen in heart valve disease, which may lead to low systolic blood pressure. Therefore, the measurement of blood pressure differential is also a certain reference value, often indicating some diseases, it refers to a difference between systolic and diastolic blood pressure, systolic pressure minus diastolic pressure is the blood pressure differential.