Lung cancer is a major cause of morbidity and mortality, which is the rapidest increased type of cancer in China with over 5 times incidence rate increase during the past 30 years. Tyrosine kinase inhibitors (TKIs) of the epidermal growth factor receptor (EGFR) have been widely used for the treatment of patients with non-small cell lung cancer(NSCLC). Icotinib is a novel EGFR-TKI developed by a group of Chinese scientists and clinician. Icotinib appears to be non-inferior to Gefitinib in terms of efficacy, better in terms of safety, and larger of therapeutic window in phase I-III trials. In this study, an open , single-center, single arm phase IV trial was designed to evaluate the safety and efficacy of dose escalation of icotinib in the treatment of advanced NSCLC patients after failure with routine dose. PFS (progress free survival) is the primary end-point with OS (overall survival), ORR (objective response), TTP (time to progress), HRQOL and safety as the secondary end-point.