Hypertension does not occur for no reason. Some patients suddenly find their blood pressure elevated when they undergo a physical examination, but in fact, many hypertension occurs for a reason, divided into primary and secondary causes. Primary hypertension is more common in clinical practice and is associated with genetics, obesity, mental stress, excessive stress, staying up late, etc. Secondary hypertension is often secondary to other diseases that cause elevated blood pressure, the most common ones such as adrenal cortex or medullary hyperplasia or tumors, renal artery stenosis, increased cortisol, etc. cause elevated blood pressure. Therefore, once patients find elevated blood pressure, they should actively monitor and track their blood pressure, and if necessary, go to improve 24-hour ambulatory blood pressure to further clarify the presence of hypertension, to rule out white coat hypertension. If once hypertension is diagnosed it is also important to actively look for the cause and to identify the risk factors for hypertension, the absence of target organ damage and clinical complications through tests to determine antihypertensive strategies and improve clinical outcomes.