Abstract: Objective To investigate the expression and clinical significance of Toll-like re-ceptor 4 (TLR4)and nuclear factor-kappaB (NF-κB)in non-small cell lung cancer (NSCLC)tissue. Methods The immunohistochemical SP method was used to examine the protein expressions of TLR4 and NF-κB in 58 cases of NSCLC tissue and tissue adjacent to cancer.The relationship between pro-tein expressions of TLR4 and NF-κB and NSCLC clinical pathological characteristics as well as both correlations were analyzed.Results The positive rates of TLR4 and NF-κB protein in NSCLC tissue weresignificantly higher than in the tissue adjacent to cancer (6 0 .3 % vs .1 5 .5 % and 6 7 .2 % vs . 8.6%),with statistical significance.There was statistical significance by comparison to the positive rates of TLR4 protein in different differentiated tissues and NF-κB protein expression in different histo-logical types in NSCLC,and the positive rate of NF-κB protein in adenocarcinoma was obviously higher than in squamous carcinoma (80.6% vs.51.9%).The expression of TLR4 protein was closely asso-ciated with that of NF-κB protein.Conclusion TLR4 and NF-κB may participate in NSCLC infiltra-tion and metastasis,which provides a certain references for judging the differentiated and malignant de-grees as well as histological types in NSCLC tissue.