Objective To investigate the levels and clinical significance of pentraxin 3 (PTX3) and high sensitive C-reactive protein(Hs-CRP) in patients with chronic obstructive pulmonary disease (COPD).Methods Seventy COPD patients at acute exacerbation stage were selected as the acute exacerbation group,70 COPD patients at disease remission stage were selected as remission group,and 70 healthy subjects were selected as control group.According to pulmonary function,70 COPD patients at acute exacerbation stage were divided into mild-to-moderate group(37 cases) and severe-to-very severe group (33 cases).The serum levels of PTX3,Hs-CRP,white blood cell count (WBC),neutrophils (NE) were measured.Results The serum levels of PTX3,Hs-CRP,WBC and NE of the acute exacerbation group and remission group [(0.89 ± 0.38) μg/L,(52.14 ± 4.25) mg/L,(12.13 ± 4.78) ×109/L,(79.68 ± 9.02)％;(0.47 ± 0.12) μg/L,(10.28 ± 3.42) mg/L,(8.02 ± 3.24) × 109/L,(67.24 ± 8.02) ％] were higher than those of the control group [(0.18 ± 0.04) μg/L,(4.42 ± 2.02) mg/L,(4.97 ± 2.57) × 109/L,(63.38 ± 8.79) ％] (t =213.252,245.168,48.647,53.241;121.426,124.352,21.425,24.352,all P ＜0.05).The serum levels of PTX3,Hs-CRP,WBC and NE of the acute exacerbation group were higher than those of the remission group (t =89.435,93.214,18.325,16.325,all P ＜ 0.05).In COPD patients at acute exacerbation stage,the serum levels of PTX3,Hs-CRP,WBC and NE of the mild-to-moderate group and severe-to-very severe group [(0.77 ±0.32) μg/L,(41.23 ±3.74) mg/L,(8.24 ±4.48) × 109/L,(71.54 ±8.73)％;(1.13 ±0.43) μg/L,(59.32 ± 4.65) mg/L,(14.21 ± 5.02) × 109/L,(87.96 ± 9.36) ％] were significantly higher than those of the control group [(0.18 ± 0.04) μg/L,(4.42 ± 2.02) mg/L,(4.97 ± 2.57) × 109/L,(63.38 ± 8.79) ％](t =43.253,314.265,53.241,67.324;47.315,289.253,46.572,63.241,all P ＜ 0.05).The serum levels of PTX3,Hs-CRP,WBC and NE of the severe-to-very severe group were higher than those of the mild-to-moderate group (t =38.942,267.425,46.537,58.932,all P ＜ 0.05).There was positive correlation between serum PTX3 and Hs-CRP,WBC,NE in COPD patients at acute exacerbation stage (r =0.532,0.498,0.697,all P ＜ 0.05).The serum Hs-CRP was positively correlated with WBC and NE (r =0.542,0.713,P ＜ 0.05).Conclusion Serum levels of PTX3 and Hs-CRP are elevated in patients with COPD.The serum levels of PTX3 and Hs-CRP are associated with disease severity.