It is well known that SNPs that are located in the promoter, 5'-untranslated region (5'-UTR), exons, and 3'-UTR of gene sequences may influence the expression or the structure of genes and thus supported to be putatively functional [20,25].The putatively functional SNPs of PXR may affect the expression or function of PXR. On account of the fact that PXR may play roles in lung carcinogenesis, we hypothesized that these putatively functional SNPs in the PXR gene were associated with lung cancer susceptibility in Chinese. This evidence concerns the gene NR1I2 and lung cancer.