Abstract: Objective To evaluate the efficacy and toxicity of Gefitinib in the treatment of advanced adenocarcinoma of lung. Methods Fifty five patients with stage Ⅳadenocarcinoma of the lung who had failed or not tolerated or refused chemotherapy received 250mg oral doses of Gefitinib once a day，until disease progression or development to intolerable toxic reaction. Results There was no complete regression observed,partial response(PR) rate was 38.2%(21/55),stable disease (SD) 27.3% (15/55),disease control rate (CR+PR+SD)65.5%, progression of disease(PD) 34.5% (19/55) and median time to tumor progression(TTP) was 7.2 month. One year survival rate was 43.6%.The drug-related adverse reactions were skin rash 28(50.9%),dry skin 19(34.5%),diarrhea 14(25.5%),nausea 7(12.7%),and hepatic dysfunction (ALT and AST increase) 1 (1.8%). Conclusion Gefitinib is active in patients with advanced adenocarcinoma of lung. It is well tolerated with minimal side effects. All patients have well compliance and tolerability.