Abstract: Objective 　To investigate the antitumor effect s and adverse reactions of gefitinib in t reating ad2 vanced non2small cell lung cancer. Methods 　Forty2two patient s who were right pathologically diagnosed with advanced non2small cell lung cancer and failed prior chemotherapy and radiotherapy were adminis2 tered orally with gefitinib 250 mg, once a day until cancer progressed or severe toxicity occurred. The ef2 ficacy adverse reactions of gefitinib survival and disease progression time of patient s were observed. Re2 sults 　Among the 42 patient s, 1 cases got complete response (CR), 13 partial response ( PR), 16 stable disease (SD) and 12 progression disease ( PD) . The total response rate was 33. 33 % and the disease con2 t rol rate was 71. 43 %. The median time to progression was 6. 0 months and the median survival time was 9. 2 months. The major adverse reactions of gefitinib included rash, itching and diarrhea. Conclusion 　Gefitinib was effective and safe for patient s with advanced non2small cell lung cancer who failed prior chemotherapy and radiotherapy. The toxicities of gefitinib were tolerable. Gefitinib is a good choice for the patient s with advanced non2small cell lung cancer who were resistant to chemotherapy and radiothera2 py.