Abstract: OBJECTIVE To explore the association of pulmonary Aspergillus infection in chronic obstructive pulmonary disease（COPD） patients with lung function single nucleotide polymorphism of pentraxin-3（PTX3） gene. METHODS A total of 60 COPD patients complicated with pulmonary Aspergillus infection who were treated in Jiangxi Armed Police Corps Hospital from Jan 2019 to May 2020 were chosen as the study group, meanwhile, 80 COPD patients who were not complicated with pulmonary infection were assigned as the control group. The lung function index forced expiratory volume in 1 second（FEV1） was detected by using lung function tester, the polymorphism of PTX3 gene at rs1840680 locus was detected by using restriction fragment length polymorphism polymerase chain method, the serum PTX3 level was determined by means of enzyme-linked immunosorbent assay, and the correlation between the polymorphism of PTX3 gene at rs1840680 locus and the susceptibility to pulmonary Aspergillus infection and lung function of the COPD patients was observed. RESULTS The frequencies of genotypes AA at rs1840680 locus of PTX3 gene and allele A of the study group were respectively, 21.67% and 43.33%,significantly higher than those of the control group（P＜0.05）; there was no significant difference in the frequency of genotype GG,GA between the two groups. Logistic regression analysis showed that the genotype AA and allele A were the independent risk factors for the pulmonary Aspergillus infection in the COPD patients（P＜0.05）. In the study group, there was no significant difference in the distribution of genotypes at rs1840680 locus of PTX3 gene between the patients with global initiative for chronic obstructive pulmonary disease（GOLD） ranging from Ⅰ to Ⅱ and the patients with GOLD ranging from Ⅲ to Ⅳ. The serum PTX3 level of the patients with GOLD ranging from Ⅰ to Ⅱ was（79.94±19.34）ng/ml, significantly lower than（111.82±28.62）ng/ml of the patients with GOLD ranging from Ⅲ to Ⅳ（P＜0.05）. . CONCLUSION The polymorphism at rs1840680 locus of PTX3 gene is associated with the pulmonary Aspergillus infection in the COPD patients, and the allele A is a susceptible gene but was not associated with the lung function.