The significance of the 4 tests for hypertension is that through the 4 tests, it is possible to clarify to a certain extent whether or not an individual’s elevated blood pressure is due to secondary factors, and it is one of the most important indicators for the differentiation between secondary and primary hypertension, which can provide data support for the physician’s subsequent treatment of hypertension. The 4 tests for hypertension mainly include aldosterone test, renin activity test, angiotensin test below 37℃, and angiotensin test below 4℃. The values of these tests are used to understand whether an individual has primary aldosteronism, reninoma, and other diseases that predispose to secondary hypertension. The Hypertension 4 is usually done through a blood test, and the physician is able to use the results to type hypertension for subsequent diagnosis and treatment.