Brain natriuretic peptide precursor (BNP) is a kind of natriuretic peptide secreted by heart, which is a peptide composed of amino acid residues, and its normal value is usually less than 125 pg/ml. It is the most sensitive indicator in acute heart failure examination and can detect heart failure symptoms at an early stage. It can be influenced by infection, arrhythmia, myocardial infarction, age, renal function and other factors. If the laboratory results are increased, the reliability of the index abnormality needs to be considered after considering various factors. As for its physiological effects, brain natriuretic peptide precursors mainly play the role of regulating blood pressure and blood volume balance, and can be mildly diuretic.