Objective To investigate the correlation between serum laminin (LN),type collagen (ⅣC),type procollagen N-terminal peptide (PⅢNP),hyaluronic acid (HA) and the severity as well as the prognosis of idiopathic pulmonary fibrosis (IPF).Methods From February 2015 to July 2016,160 IPF patients and 160 healthy subjects as controls were enrolled in this retrospective study.Serum LN,ⅣC,PⅢNP,and HA were analyzed in IPF patients and healthy controls.Pulmonary function test and chest high resolution computed tomography (HRCT) were carried out in IPF patients.Demographics and clinical characteristics,the percentage of forced vital capacity in the prediction value (FVC％pred),the percentage of diffusing capacity of the lung for carbon monoxide in the prediction value (DLCO％pred),and HRCTscore were collected.IPF patients were followed up.Results (1)There were no significant difference between two groups in age and sex ratio.The proportion of smoker in IPF patients was significantly higher than that in healthy controls(P ＜ 0.01).(2)Serum LN(P ＜ 0.01),ⅣC(P ＜ 0.01),PⅢNP(P ＜ 0.01),and HA(P ＜ 0.01) were significantly increased in the patients with IPF compared with the healthy controls.(3)Serum LN,ⅣC,PⅢNP,and HA of IPF patients positively correlated with HRCT score,all P ＜ 0.01,and negatively correlated with FVC％pred and DLCO％pred (all P ＜ 0.05).(4)Serum LN(P ＜ 0.01),ⅣC(P ＜ 0.05),PⅢNP(P ＜ 0.01),and HA(P ＜ 0.01) in acute exacerbation IPF patients were significantly higher than those in the stable IPF patients.(5)Serum LN(P ＜ 0.01),ⅣC(P ＜0.01),PⅢNP(P ＜ 0.01),and HA(P ＜ 0.01) in the survived patients were significantly lower than those inthe dead patients.Conclusions Serum LN,ⅣC,PⅢNP,and HA may reflect IPF prognosis and the severity of IPF.