Gefitinib and erlotinib are first-generation, small, molecular inhibitors of the epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI). Even as these drugs have led to a paradigm shift in the treatment of advanced non-small cell lung cancer (NSCLC), drug-induced adverse effects are commonly seen. We experienced two cases of NSCLC patients who developed erlotinib-induced eyelid erosion and were then successfully treated with gefitinib, without recurrence of toxicity or disease progression. As far as we had investigated, this is the first report documenting the successful cases treated with gefitinib after erlotinib-related severe eyelid erosion.