Abstract: Objective To examine the relationship of glutathione S-transferase M1(GSTM1)and T1(GSTT1)with the susceptibility to lung cancer in women.Methods The case-control study was conducted among 42 lung cancer and 55 healthy controls.The genetic polymorphisms of GSTM1 and GSTT1 were detected with the method of multiplex polymerase chain reaction.Stratification analysis was used to assess the interaction between GSTM1 and GSTT1 null genotypes.Results The frequences of GSTM1 and GSTT1 null genotypes were 66.7% and 45.2% respectively in lung cancer,while 54.5% and 38.2% in healthy controls.There was no obvious difference between lung cancer and healthy controls(P>0.05).But in nonsmoking women subjects the frequence of GSTM1 null genotype was significantly different between lung cancer and healthy controls(P=0.046),and the null genotype was associated with an increased risk of lung cancer in nonsmoking women.But GSTT1 null genotype was not overrepresented in non-smoking women with lung cancer(P=0.557)compared with controls.The results from interaction analysis showed GSTM1 null genotypes combined with GSTT1 null genotypes did not have interaction on the risk of lung cancer.Conclusion GSTM1 deletion may be an importanthost risk for lung cancer in nonsmoking women,whereas GSTT1 deletion is not associated with the risk to lung cancer in women.Furthermore,there was no significant interaction between GSTM1 and GSTT1 null genotypes which could affect the susceptibility of women to lung cancer.