The purpose of drug therapy is not only to lower blood pressure itself, but also to provide important protection to target organs such as heart, brain and kidney. Because of the long-term elevation of blood pressure, although at first only some patients may experience dizziness, headache, chest tightness and other discomfort caused by elevated blood pressure, a small number of patients may not even have any symptoms; however, if not given timely antihypertensive treatment, blood pressure will continue to increase, eventually leading to serious damage to the heart, brain, kidney and blood vessels, which may lead to heart failure, myocardial infarction, cerebral thrombosis, cerebral hemorrhage, kidney function The serious consequences such as heart failure, myocardial infarction, cerebral thrombosis, cerebral hemorrhage, renal insufficiency, etc. Therefore, to some extent, taking antihypertensive drugs is to strengthen the protection of heart, brain and kidney target organs, reduce the occurrence of cardiovascular disease, and achieve the purpose of protecting people’s health. Current studies have shown that antihypertensive drugs have significant benefits in reversing left ventricular hypertrophy, reducing the incidence of stroke, as well as reducing new onset diabetes, reducing urinary microalbumin, and delaying further deterioration of renal function in many ways. Therefore, lowering blood pressure to the standard is fundamental to the prevention of cardiovascular disease. The protective effects of antihypertensive drugs on the heart, brain and kidney have been confirmed by large-scale clinical studies in hypertensive patients and the general population including those with high values of normal blood pressure. The cardio-, cerebro- and renal-protective effects of each class of antihypertensive drugs have their own characteristics. For example, calcium antagonists have a better effect on anti-atherosclerosis, angiotensin-converting enzyme inhibitors can reverse left ventricular hypertrophy and vascular remodeling, and the newer angiotensin II receptor blockers have better efficacy in reversing left ventricular hypertrophy, reducing new-onset diabetes, and delaying further deterioration of renal function.