Background: We previously reported the adverse events and objective responses in a multicenter phase II study of high-dose chemoradiotherapy. This is a final analysis of the pattern of recurrences, progression free survival (PFS) and OS. Methods: Patients with stage III NSCLC were eligible if they met the following key criteria: age between 20 and 74 years, PS 0-1 and V₂₀≤ 30%. Participants received 3-4 cycles of CDDP (80 mg/m² day 1) and VNR (20 mg/m²days 1 and 8) every 4 weeks. The 3D-RT was administered at a total dose of 72 Gy divided into 36 fractions from day 1 chemotherapy. The primary endpoint was the 2-year survival rate and the planned sample size was 60 to reject the rate of 45% under the expectation of 65% with a power of 90% and an alpha error of 5%. Results: Thirty-one patients were enrolled between 2009 and 2011. The median follow-up time (range) was 51.4 (28.8-65.6) months at the point of data cut-off. This trial was terminated early due to the slow accrual and appearance of grade 5 pulmonary toxicities in 2 patients. There were 25 men and 6 women with a median (range) age of 59 (32-72) years. Of the 25, 23 had adenocarcinoma and 21 had stage IIIA disease. The median (range) V₂₀value was 20 (9-30). Among the 20 patients showing disease progression, in-field failures were observed in 5 (25%) patients as the first relapse and a further 4 patients (9 [45%] patients in total) during the follow-up period. The 2-, 3-, and 5-year PFS rates (95% CI) were 44.9% (27.1-61.2), 34.6% (18.5-51.2), and 34.6% (18.5-51.2), respectively. The 2-, 3-, and 5-year OS rates (95% CI) were 64.5% (45.2-78.5), 51.2% (32.6-67.1), and 43.8% (25.8-60.5), respectively. The median PFS and median survival time were 17.1 months and 41.2 months, respectively. Conclusions: The higher TRT dose associated both with an unacceptable incidence of pulmonary toxicities and with relatively better long-term survival. Development of a better strategy is warranted to obtain both a better outcome and tolerable pulmonary toxicities. Clinical trial information: UMIN000001743.