Intermittent and Maintenance of Icotinib in Combination With Pemetrexed/Carboplatin Compared With Icotinib Single Drug in Ⅲb/IV Non Small Cell Lung Cancer With Epidermal Growth Factor Receptor (EGFR) Mutation

Inclusion Criteria: * Present with histologically proven diagnosis of non-Squamous NSCLC Stage IIIB or IV as defined by the American Joint Committee on Cancer Staging Criteria for Lung Cancer, that is not amenable to curative therapy, such as surgery or radiotherapy and so on. * Confirmed activating mutation of EGFR-ie, an exon 19 deletion or an exon 21 L858R point mutation. * Measurable lesions according to RECIST 1.1 criteria. * Patients between 18 and 75 years of age. * Eastern Cooperative Oncology Group(ECOG) performance status of 0 or 1. * Estimated life expectancy of ≥12 weeks. * Haematological stable: ANC \> 1.5; PLT \> 100; HGB \> 90 g/L. * Adequate liver function: total bilirubin \< 1.5 x ULN; AST and ALT \< 2.5 x ULN (without liver metastasis); or AST and ALT \< 5 x ULN (with liver metastasis). * Adequate renal function: creatinine \< 1.5 x ULN; CCR \>= 50ml/min; and urine protein \< 2+; for the patients with urine protein \>= 2+, 24 hours total urine protein \<= 1g. * INR \<= 1.5; aPTT \< 1.5 x ULN, within 7 days before treatment. * For female patients, pregnancy test (blood or urine) needs to be done within 7 days before treatment; if negative, patients need to be consented for proper contraception throughout the treatment and 8 weeks after the completion of treatment. For male patients, they also need to be consented for proper contraception throughout the treatment and 8 weeks after the completion of treatment. * Signed informed consent document on file. * Patient compliance and geographic proximity that allow adequate follow up. Exclusion Criteria: * Histology is confirmed to be squamous cell carcinoma, mixed NSCLC and SCLC, or squamous cell carcinoma dominant adenosquamous carcinoma. * Patients previously had targeting HER therapy, including erlotinib, gefitinib, cetuximab，trastuzumab, etc. * Patients previously had systemic therapy for NSCLC before study, including cytotoxic medicine, target therapy, or other medicines in a clinical trial. * Physiological incompetence with upper gastrointestinal tract, or malabsorption syndrome, or intolerance of oral drugs, or active peptic ulceration. * Clinically moderate to severe COPD, active ILD or other pulmonary diseases defined by researchers. * Uncontrolled ocular inflammation or infection, or other conditions that could lead to ocular inflammation or infection. * Conditions or risk factors that contraindicate the research medicines. * Any unsteady systematic diseases, including active infection, uncontrolled high blood pressure, unstable angina, recent angina (within 3 months), congestive heart failure, ischemic heart diseases (within 6 months), severe arrhythmia， severe liver/renal/metabolic diseases. * Known HIV infection. * Unhealed wound, active peptic ulceration or fracture. * Pregnancy or lactation. * Female patients who refuse contraception throughout treatment and 6 months after the treatment; male patients who refuse contraception throughout treatment and 90 days after the treatment. * Known severe hypersensitivity to Icotinib, Pemetrexed or Carboplatin. * Patients with esophago-tracheal fistula. * Pleural effusion or pericardiac effusion that cannot be controlled by drainage or other procedures. * Inability to comply with protocol or study procedures. * A serious concomitant systemic disorder that, in the opinion of the investigator, would compromise the patient's ability to complete the study. * Patients had other malignancies apart from NSCLC, except cervical cancer in situ, skin basal cell carcinoma or squamous cell carcinoma, prostate cancer or breast ductal carcinoma in situ that have been adequately treated.