In the 1997 revision of the TNM staging system for lung cancer, patients with T3N0M0 disease were moved from stage IIIA to stage IIB since these patients have a better prognosis. Despite this modification, the local lymph node metastasis remained the most important prognostic factor in patients with lung cancer. The present study aimed to evaluate the prognosis of patients with T3N1 disease as compared with that of patients with stages IIIA and IIB disease. During 7-year period, 313 patients with non-small cell lung cancer (297 men, 16 women) who had resection were enrolled. The patients were staged according the 2007 revision of Lung Cancer Staging by American Joint Committee on Cancer. The Kaplan-Meier statistics was used for survival analysis, and comparisons were made using Cox proportional hazard method. The 5-year survival of patients with stage IIIA disease excluding T3N1 patients was 40%, whereas the survival of the patients with stage IIB disease was 66% at 5 years. The 5-year survival rates of stage III T3N1 patients (single-station N1) was found to be higher than those of patients with stage IIIA disease (excluding pT3N1 patients, P = 0.04), while those were found to be similar with those of patients with stage IIB disease (P = 0.4). Survival of the present cohort of patients with T3N1M0 disease represented the survival of IIB disease rather than IIIA non-small cell lung cancer. Further studies are needed to suggest further revisions in the recent staging system regarding T3N1MO disease.