Abstract: Objective: To observe the effect of Iressa on patients with advanced non-small cell lung cancer（NSCLC）.Methods: Thirty patients with stage Ⅲ-Ⅳ NSCLC pathologically or cytologically proved were enrolled in this study.Orally Iressa 250mg daily were given to patients with advanced NSCLC until severe toxicity or disease progress occurred,CT scan was performed for response assessment by month.Results: Among the 30 patients,0 complete response（CR）and 8 partial response（PR）were observed,15 stable disease,7 progress disease.The overall response rate was 26.7% and disease control rate including both tumor response and stable disease was 76.7%.Median time to progress of entire group was 4 months.Median survival time was 6.5 months.Female had higher response rate than male.The main toxicity of Iressa was skin toxicity（rash） and diarrhea.Conclusion: Monotherapy using Iressa is effective and tolerable for the patients with advanced NSCLC who were intolerable or failed prior radiotherapy and chemotherapy.