The prognostic and predictive value of pre-treatment serum levels of carcinoembryonic antigen (CEA) and cytokeratin-19 fragments (CYFRA 21-1) were assessed in advanced non-small cell lung cancer (NSCLC) patients treated with gefitinib or erlotinib. Pre-treatment CEA and CYFRA 21-1 levels were measured in 123 advanced NSCLC patients receiving gefitinib or erlotinib. High CEA levels (h-CEA) were significantly associated with females, patients with adenocarcinoma and non-smokers. Low CYFRA 21-1 levels (l-CYFRA 21-1) were significantly associated with a good performance status (ECOG PS 0-1). The overall response rate (RR) was 27.6%, and a higher RR was associated with adenocarcinoma, h-CEA, and epidermal growth factor receptor (EGFR) mutation. Patients with h-CEA had significantly longer progression-free survival (PFS) (P=0.021). Patients with l-CYFRA 21-1 had significantly longer PFS and overall survival (OS) (P=0.006 and P<0.001, respectively). Notably, h-CEA and l-CYFRA 21-1 levels were associated with good prognosis in patients with unknown EGFR mutation status or patients with squamous cell carcinoma (P=0.021 and P=015, respectively). A good ECOG PS (HR=0.45, P=0.017), h-CEA (HR=0.41, P=0.007), l-CYFRA 21-1 (HR=0.52, P=0.025), and an EGFR mutation (HR=0.22, P<0.001) were independently predictive of a longer PFS. A good ECOG PS (HR=0.52, P=0.018), l-CYFRA 21-1 (HR=0.36, P=0.004), and EGFR mutation (HR=0.53, P=0.051) were independently predictive of longer OS. h-CEA and l-CYFRA 21-1 may be prognostic and predictive serum markers for higher response and longer survival in patients with advanced NSCLC receiving gefitinib or erlotinib, particularly in patients with unknown EGFR mutation status or patients with squamous cell carcinoma.