Abstract: Objective To observe the clinical manifestation，quality of life（QOL） and followup survival of patients with non-small cell lung cancer（NSCLC）who had initial response to gefitinib for more than 6 months and maintained administration of the regimen even after failure of gefitinib. Methods Gefitinib was taken orally at a dosage of 250 mg daily. The NSCLC patients who had been administrated the regimen successfully more than 6 months were divided into the trail group（whose disease progressed, n=39） and the control group（whose disease didn't progress, n=49）. The QOL for patients with Karnofsky Performance Status Scale（KPS） and Functional Living Index Cancer（FLIC） were evaluated. The follow-up survival of the target lesions progression and the non-target lesions progression were calculated. Results The favorable scores of KPS and FLIC were still kept on 1.0-24.0 months to the patients in the trail group，and the median time was 6.0 months. KPS and FLIC scores were compared by the two groups，and the differences had no significance（Z=-0.976，P=0,329； Z=-0,029，P=0,977）. In the trail group，during the period of initial progress to disease flare and in the period of disease flare to death，the scores of KPS were 85.00±7.31 and 48.00±9.25（P＜0.001）；and the scores of FLIC were 121.24±18.16 and 75.57±21.45（P＜0.001）. The median follow-up survival of patients with the target lesion progress and non-target lesions progress were 7.0 months and 10.0 months in the trail group，and the difference was significant（P=0.018）. Conclusion The patients with NSCLC could gain clinical benefits from continuing the administration of gefitinib，who acquired resistance to the regimen in spite of initial responses to it，especially for the patients with non-target lesion progress.