Objective: To investigate the relationship between the genetic polymorphism of CYP1A1 and the genetic susceptibility to lung cancer as well as to study the effects of the methylation in p16 gene on the risk of lung cancer in a Chinese population. Methods: A case control study was conducted among 47 cases of lung cancer and 94 controls. The genetic polymorphism of CYP1A1 was tested with method of PCR-RFLP, and a methylation-specific PCR (MSP) was performed to detect p16 methylation. Results: It showed that there was no significant difference in frequencies of the genotypes of CYP1A1 between the two groups (P ＞ 0.05). Synergistic effects were not found between smoking and CYP1A1. Methylated p16 gene was found in 44.7% (21/47) of lung cancer tissues and in 17.0% (8/47) of normal lung tissues with significant difference (P ＜0.05). Conclusion: The genetic polymorphism of CYP1A1 does not increase the risk of lung cancer in a Chinese population.The methylation in p16 gene may be the most common mechanism to inactivate p16 gene in lung cancer, and is not significantly associated with genotype of CYP1A1.