Abstract: OBJECTIVE To explore the relationship between platelet endothelial aggregation receptor-1（PEAR1） polymorphism and pulmonary infection in patients with acute pulmonary embolism（APE）. METHODS Total of 102 APE patients admitted to the Mindong Hospital of Fujian Medical University from Dec 2018 to Dec 2020 were enrolled. According to whether lung infection occurred during the hospitalization, they were divided into 39 cases in the lung infection group and 63 cases in the non-infected group. Coagulation function indicators including prothrombin time（PT）, activated partial thromboplastin time（APTT）, thrombin time（TT） and fibrinogen（FIB） were detected. Real-time fluorescent quantitative polymerase chain reaction was used to detect single nucleotide polymorphism in PEAR1 genes sites（rs12041331, rs2768759）. RESULTS There was no significant difference in the genotype distribution of rs2768759 between the pulmonary infection group and the uninfected group. The frequency of AA at rs12041331 site in the lung infection group was significantly higher than that in the uninfected group（P＜0.05）. The coagulation function indexes such as PT, APTT and FIB in the lung infection group were significantly higher than those in the uninfected group, while TT level was significantly lower than that in the uninfected group（P＜0.05）. The PT, APTT and FIB levels in patients with type AA at PEAR1 rs12041331 in the lung infection group were significantly higher than those with the GG/GA type, while the level of TT was lower（P＜0.05）. CONCLUSION The increase of susceptibility to pulmonary infection in the APE patients may be associated with the AA genotype at rs12041331 locus of PEAR1, and the locus may lead to the decline of pulmonary anti-infection ability by affecting the coagulation function.