Objective:To establish a lung cancer phage-peptide library and to screen for biomarkers for early detection of lung cancer.Methods: A phage display library was constructed using 30 lung-cancer tissue samples from Changhai Hospital. Protein-A/G agarose was used to enrich IgG from control sera as well as lung cancer sera. Five biopannings were carried out for enrichment of lung cancer-specific phage clones. Five hundred phage clones were randomly selected,those with D>2.0( lung cancer plasma pool v.s. control plasma pool)were selected for DNA sequencing and protein prediction. Results: (1) The recombination rate of the phage library was 60%,with the average phage titer being 3.0×106 pfu and a volume being 9.0×106 pfu.(2) Of 19 phage colonies selected by ELISA and sequenced,9 were cancer-related genes,8 with unknown function,and 2 were not related to cancer. Conclusion: The screened genes in the phage colonies might serve as biomarkers for the early diagnosis of lung cancer.