Abstract: Objective Xeroderma pigmentosum group D(XPD)is one of the important DNA repair genes.XPD polymorphism at Lys751Gln site and Asp312Asn site have been shown to alter XPD protein function,modulate DNA repair capacity and therefore affect cancer risk.The aim of this study is to explore the relationship between XPD polymorphism and susceptibility to lung cancer in nonsmoking female by a population-based case-control study.Methods There were 222 female patients who were diagnosed with lung cancer from Heilongjiang Tumor Hospital,and the control group included 222 healthy volunteers who were obtained from community centers.XPD genotypes of cases and controls were determined by PCR RFLP method.Unconditional logistic regression analysis was performed to calculate the odds ratios(OR)with 95 confidence intervals(CI)for estimating the association between certain genotypes and lung cancer.Results All of the subjects in this study were nonsmoking females who living in Harbin more than 30 years.The risk of lung cancer was higher in those with the Lys/Gln or Gin/Gin genotype than in those with the Lys/Iys genotype and adjusted OR was 3.36(95 CI:2.29-4.90)and in those with the Asn/Asn or Asp/Asn genotype than in those with the Asp/Asp genotype and adjusted OR was 1.83(95 CI:1.16-2.91).Conclusion The findings indicated that the Lys751Gln and Asp312Asn polymorphisms in XPD gene are associated with the risk of lung cancer in nonsmoking females.