Abstract: Objective: To investigate the association between the genetic polymorphism of GSTT1 and the susceptibility to lung cancer and a synergetic interactions between smoking and genetic polymorphisms on lung cancer susceptibility.Methods: A case-control study and PCR—RFLP techniques were used to identify GSTT1 genotype in 100 cases of lung cancer and 135 controls.Results: The frequency of GSTT1(-) genotype in lung cancer group and controls was 57%(57/100) and 41.5%(56/135) respectively(P=0.016). There were no gender differences of GSTT1 (-) genotype distribution. In people with GSTT1(-) genotype ,smoking markedly increased the risk for lung cancer(P=0.016).In smokers，GSTT1 (-) genotype significantly increased the risk for lung cancer(P=0.006).In smokers≥ 20 packyears，GSTT1 (-) genotype remarkably increase the risk of lung cancer (P=0.002).Conclusions:The distribution frequency of GSTT1(-) genotype was higher in lung cancer，which Might increase the genetic susceptibility to lung cancer．There might be a synergetic interaction between smoking and GSTT1(-) genotype．

Key words: GSTT1, Gene Polymorphism, Lung Cancer, Susceptibility, smoke