Polymorphisms in metabolic genes encoding phase I and phase II enzymes are thought to modulate the risk of lung cancer via changes in enzymatic activity. Recently, the effect of these metabolic enzymes and their interaction with environmental factors has been studied in both smokers and also never-smokers, since never-smokers are a good model in which to study genetic susceptibility at low-dose carcinogen exposure. Here, we investigated the association of CYP1A1 Ile462Val, CYP1B1 Leu432Val, GSTP1 Ile105Val, MPO G-463A polymorphisms and lung cancer risk in never-smoking Korean women. In this case-control study of 213 lung cancer patients and 213 age-matched healthy controls, we found that carrying one variant allele of the CYP1A1 Ile462Val polymorphism was associated with a significantly decreased risk of lung adenocarcinoma (adjusted odds ratio (OR)=0.63; 95% confidence interval (CI), 0.41-0.99). Furthermore, the combination of risk genotypes of CYP1B1 Leu432Val with CYP1A1 Ile462Val was associated with the risk of lung adenocarcinoma (adjusted OR=2.16; 95% CI, 1.02-4.57) as well as overall lung cancer (adjusted OR=2.23; 95% CI 1.01-4.89). The polymorphisms of GSTP1 Ile105Val and MPO G-463A showed no significant association with lung cancer. Theses results suggest that the CYP1A1 Ile462Val polymorphism is associated with a reduced risk of lung adenocarcinoma in never-smoking Korean women, whereas specific combinations of variant genotypes for metabolic enzymes increase lung cancer risk considerably.