The purpose of this study was to investigate the correlation between idiopathic pulmonary fibrosis(IPF)and tumor markers to provide evidence for early screening of precancerous lesions.In our hospital from July 2017 to May 2019,40 patients with IPF treatment were selected as the IPF group,and 40 patients with idiopathic pulmonary fibrosis with lung cancer(IPF-LC)were selected as the IPF-LC group.In the same period,40 healthy physical examinees were used as control group.Different types of patients in the IPF-LC group were divided into lung adenocarcinoma group,small cell lung cancer group and l squamous carcinoma group.The expression levels of tumor markers were detected in the three groups,the positive rates of tumor markers in IPF group,IPF-LC group and their subgroups were compared.The results showed that the levels of neuron specific enolase(NSE),antigen CYFRA211,carcinogenic antigen(CEA)and cancer antigen 125(CA125)in IPF and IPF-LC groups were significantly higher than those in control group(P<0.05).There was no significant difference in CEA and CYFRA211 between IPF-LC group and IPF group.The level of NSE in IPF-LC group was significantly higher than that in IPF group,while the level of CA125 was significantly lower than that in IPF group(P<0.0.5).The difference of positive rate of NES and CA125 in IPF-LC group and IFP group was statistically significant(P<0.05),there was no statistically significant difference in the positive rate of other indicators(P>0.05)The NSE positive rate of IPF group was significantly lower than that of IPF-LC group(P<0.05),the positive rates of other tumor markers were significantly lower than those of each subgroup of IPF-LC group(P<0.05).Therefore,tumor markers in IPF patients showed different degrees of increase,which is worthy of clinical attention.Among them,NSE can be used as an early screening indicator for IPF precancerous lesions.