Objective    To identify the correlation of the serum carcinoembryonic antigen (CEA) level and the therapeutic effect of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) as a gene targeted drug in advanced non-small cell lung cancer (NSCLC).     Methods     We retrospectively reviewed 88 NSCLC patients

including 69 adenocarcinoma and 19 non-adenocarcinoma who admitted in our hospitals from July 2007 to November 2010. After at least 1 cycle of chemotherapy

they begun to take Gefitinib or Erlotinib. Their therapeutic effect could be evaluated correctly and all cases had complete outcome of serum CEA. The statistical test between the serum CEA level and the therapeutic effect were performed by SPSS17.0.     Results    In the cases whose serum CEA level was lesser than 5 ng/ml

the effect rate (including complete remission and partial remission

CR + PR) was 18.2% (6/33)

the stable disease (SD)  rate was 18.2% (6/33) and the progressive disease (PD) rate was 63.6% (21/33). But in the cases whose serum CEA level was equal or higher than 5 ng/ml

the effect rate (CR+PR) was 30.9% (17/55)

the SD rate was 43.6% (24/55) and the PD rate was 25.5%（14/55). The two EGFR-TKI treatment response rates had greatly statistical difference (P=0.003). The patients who had a higher serum CEA level had a better therapeutic outcome

while for those with a low CEA level

a poor therapeutic effect was observed. Survival analysis suggested that high serum CEA level was associated with long progress free survival (PFS) and good prognosis（P=0.020，P=0.019）.     Conclusion    Serum CEA level can be regard as predictive factor for therapeutic effect and prognosis in advanced NSCLC treated with EGFR-TKI.