The AIM of this study was to identify prognostic factors in patients receiving trimodality therapy for locally advanced non-small-cell lung cancer (NSCLC). Among patients who underwent induction chemoradiotherapy (CRT) followed by surgery between 1999 and 2011 at our institution, 76 NSCLC patients with clinical (c) N2/3 stage III were enrolled in this retrospective study. Induction CRT consisted of docetaxel and cisplatin with concurrent 40-60 Gy radiation therapy. In total, 76 patients were assessed (53 men and 23 women) with 43 adenocarcinomas and 33 non-adenocarcinomas. Of the 76 patients, 44 had cStage IIIA and 32 had cStage IIIB disease. The primary tumors were located in the right upper lobe (N=33), right middle lobe (N=5), right lower lobe (N=11), left upper lobe (N=20s) and left lower lobe (N=7). For all 76 patients, lower lobe tumors were associated with a significantly shorter overall survival (OS) and disease-free survival (DFS) compared to non-lower lobe tumors (OS, P=0.022; and DFS, P=0.0007). When the analysis was limited to pathologically proven N2/3 disease prior to induction CRT (n=36), lower lobe location, compared to other locations, tended to be a poor prognostic factor (OS, P=0.068; and DFS, P=0.0075). Our results indicated that a lower lobe tumor origin is associated with unfavorable prognosis in NSCLC patients treated with induction CRT, strongly suggesting the significance of appropriate patient selection in order to maximize the benefits of trimodality therapy.