Background: Gefitinib is a first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). It was approved by the U.S. Food and Drug Administration (FDA) for clinical use in 2003. However, gefitinib has only come to China in recent years. Previous studies have not compared the efficacy and safety of domestic and imported gefitinib. Therefore, we conducted this study. Methods: This study included 227 patients with advanced non-small cell lung cancer (NSCLC) who received gefitinib treatment in four medical institutions: The First Affiliated Hospital of USTC, Division of life Sciences and Medicine, University of Science and Technology of China, Anhui Provincial Cancer Hospital, Fudan University Shanghai Cancer Center, Shandong Provincial Institute of Cancer Prevention and Jiangsu Cancer Hospital, from January 2017 to July 2018. The patients were divided into a Yiruike group (55 patients treated with domestic gefitinib, Ytruike) and an Iressa group (172 patients treated with imported gefitinib, Iressa). Because gefitinib resistance usually occurs within 8-10 months of gefitinib administration, the patients were followed up for one year to observe their conditions and compare the occurrence of adverse reactions between the two groups. Results: The two groups had no significant difference in baseline data. The median progression-free survival (PFS) of Yiruike group and that of Iressa group were 10.270 +/- 2.036 and 12.970 +/- 1.634 months, respectively. The mean PFS of Yiruike group and that of Iressa group were 12.598 +/- 1.083 and 15.958 +/- 0.987 months, respectively. The one-year disease control rate (DCR) of Yiruike group and that of Iressa group were 61.8% and 59.3%, respectively. The differences were all insignificant (P>0.05). The incidence of adverse reactions in these two groups were not significantly different. Conclusions: Yiruike was slightly superior to Iressa in terms of DCR. However, comparisons of bioequivalence and DCR were not sufficient for evaluating a drug. Other comparisons require long-term follow-up studies with a large sample size.