Abstract: Objective To explore the impact and independence of the effects of non-cardiac factors on the level of N-terminal pro-B-type natriuretic peptide (NT-proBNP), so as to determine which non-cardiac factors should be included in the correction range of NT-proBNP. Methods A retrospective study was carried out to investigate the clinical data from 231 patients in the renal department and the cardiovascular department of Jiangsu Province Hospital from February 2019 to June 2019. The patients had no cardiac insufficiency, nor combined with pulmonary hypertension, pulmonary embolism, pulmonary edema, and sepsis. Then, univariate binary logistic regression was performed to screen impact factors, while paired-samples t test was used to verify the independence of these factors, where the function was determined through curvilinear regression. Results Univariate binary logistic regression showed that obesity (OR=0.539, P=0.001, 95%CI: 0.373-0.779), anemia (OR=5.419, P=0.000, 95%CI: 3.355-9.753), and renal insufficiency (OR=2.603, P=0.000, 95%CI: 2.051-3.305) were the risk factors which caused the increase of NT-proBNP. Paired-samples t test showed that after eliminating the influence of the other two factors by pairing, renal insufficiency was the only factor which independently affected NT-proBNP (P=0.000-0.001 with different dividing standards). The result of curvilinear regression showed that NT-proBNP=5154.826*eGFR^(-0.774)(R²=0.409, P=0.000). Conclusions Renal function is an independent and strong interference factor of NT-proBNP which should be included in the correction range of NT-proBNP.