Blood pressure is divided into systolic and diastolic blood pressure, the normal range is 90-120/60-90mmHg. Therefore, systolic blood pressure is lower than 100 but greater than 90 is normal, if lower than 90 is abnormal; and diastolic blood pressure of 90-100 for the first level of hypertension, lower than 90 is normal blood pressure. 1. Systolic blood pressure: If the patient’s systolic blood pressure is lower than 100, it may be caused by physiological factors, generally some women with small body size may have low blood pressure for a long period of time, and if it doesn’t affect the blood supply of important organs, it usually doesn’t need to be treated and intervened. There is also a possibility of pathological factors, such as diarrhea, infection, malnutrition and other problems, the first time to treat the primary disease, in order to improve the symptoms of low blood pressure. 2. Diastolic blood pressure: If the patient’s diastolic blood pressure is lower than 100, it may be due to the patient’s activities, emotional excitement, and exercise in the process of low-pressure elevation, which is a compensatory performance of the human body. When the patient returns to the normal state, the blood pressure can return to normal, will not bring too much danger to the human body. However, if the patient in the resting state, the emergence of long-term low-pressure elevation, it should be considered that may be the problem of hypertension. If the blood pressure is not normal, you should seek medical attention and follow the doctor’s instructions.