Hypertension is a cardiovascular syndrome with increased systemic arterial pressure as the main clinical manifestation. In the absence of antihypertensive drugs, if the systolic blood pressure is ≥140 mmHg and (or) the diastolic blood pressure is ≥90 mmHg when measured three times on different days, it can be diagnosed as hypertension. Hypertension is the most common chronic disease and the most important risk factor for cardiovascular and cerebrovascular diseases. Its major complications such as stroke, myocardial infarction, heart failure and chronic kidney disease not only cause disability and high mortality rates. Hypertension generally refers to primary hypertension. Primary hypertension accounts for more than 90% of hypertension. The cause of hypertension is not very clear at present. The cause and pathogenesis of each individual are different, and there are large individual differences.