Objective:The aim of this study was to assess the expression of protein products of CBP(CSK-binding protein) in non-small cell lung cancer(NSCLC), to estimate their possible expression and to correlate the results of immunohistochemical analysis with various clinicopathologic parameters. Methods:The expression of CBP gene was detected by immunohistochemical S-P method in 50 cases of NSCLC tissues,50 para-cancer tissues and 10 cases of lung benign lesion tissues as control. According to immunohistochemical results, the expressions of CBP mRNA were detected by reverse transcriptase polymerase chain reaction(RT-PCR) in corresponding samples. Results:The expression level of CBP gene was found to be significantly lower in NSCLC tissues than in para-cancer tissues and lung benign lesion tissues(P < 0.05). The expression level of CBP gene was closely related to PTNM stages and lymph node involvement in Lung cancer patients(P < 0.05). Conclusion:CBP gene may play a role in the negative feedback regulation of Src-family kinases in non-small cell lung cancer, and reduction of CBP gene expression may be related to the pathogenesis and development of NSCLC.