Abstract: ObjectiveTo investigate the risk factors for lung cancer among nonsmokers. MethodsWe performed a case-control study, including 306 cases and 306 controls matched by frequency age (±3 years) and gender.The research population were interviewed to obtain ralated informations using the uniform questionnaire. Results25 exposure factors were ralated to non-smoking lung cancer by using univariate analysis. The multivariate Logistic regression showed that BMI＜18.5 ，polluted factory nearby, irritant smell after decoration, EST exposure at home, EST exposure at work, using pesticide, eating fired food,introversive character, pulmonary-operation history and family history of cancer were risk factors,while BMI≥24, eating egg (＞3 times/week )and fruit (＞3 times /week ),drinking tea, frequent exercise (two years ago) might be protective factors.We found there were the most combined effects among polluted factory nearby, irritant smell after decoration, EST exposure at home, EST exposure at work, using pesticide and family history of cancer. Conclusion The risk factors for lung cancer among nonsmokers were complex and need to be further identified.