Elderly people’s blood pressure can be high or low due to physiological factors, but also due to improper lifestyle, irregular use of antihypertensive drugs, pheochromocytoma and other disease factors. 1. Physiological factors: Normal human daily blood pressure fluctuates day and night, generally in the morning from 6 to 10 o’clock and in the afternoon from 4 to 8 o’clock there will be a small peak of blood pressure, so the blood pressure measured at different times of the day can be manifested as high and low, which is a normal phenomenon. 2. Improper lifestyle: poor mental state, excessive tension or anxiety, and sudden large changes in the rhythm of life can lead to fluctuations in blood pressure. 3. Unstandardized use of antihypertensive drugs: If you do not use antihypertensive drugs according to the doctor’s instructions, or change the time and dosage of drugs on your own, it may lead to unstable antihypertensive effect and fluctuating high and low blood pressure. 4. Disease factors: such as pheochromocytoma, can lead to endocrine disorders, paroxysmal secretion of excessive catecholamines, resulting in the emergence of high blood pressure, rapid heartbeat, the overall performance of blood pressure, generally need to be based on the size of the tumor, the location of the choice of surgical and other treatment methods. If the blood pressure of the elderly is high or low, it is recommended to consult a doctor in time to find out the cause of the disease, so as not to delay the condition.