The ratio of the rs198388 site homozygous mutation of the BNP gene in the COPD group was significantly higher than that of the control group (adjusted OR = 1.261, 95% CI = 1.091–1.396, P = 0.002), and the risk of COPD in the T allele carriers increased significantly (adjusted OR = 1.145, 95% CI = 1.055–1.232, P<0.001). The gene discussed is NPPB; the disease is chronic obstructive pulmonary disease.