To investigate the associations between vitamin D, genetic polymorphisms in the vitamin D metabolism pathway, cigarette smoke and NSCLC risk, we conducted a case-control study and utilized the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique to evaluate the single-nucleotide polymorphisms (SNPs), which were located in the protein coding and promoter regions VDR, CYP24A1, CYP27B1 and GC genes. Here, GC is linked to non-small cell lung carcinoma.