To compare the outcomes and treatment-related toxicities of two chemoradiotherapy schedules given to the patients with unresectable locally advanced non-small cell lung cancer (NSCLC): sequential chemotherapy with accelerated hypofractionated radiotherapy (SCRT), and concurrent chemotherapy with standard radiotherapy (CCRT), 68 patients from two prospective clinical trials were included. Thirty-four patients were treated with SCRT using an accelerated hypofractionated radiation schedule, 34 patients received CCRT with standard radiation. Between the two treatment groups there were no significant differences in terms of overall survival, progression-free survival (PFS), locoregional-PFS or distant metastasis-PFS. For the SCRT group, the median survival time and 2- and 4-year overall survival rates were 19 months, 38.2%, and 23.5%, respectively, and for the CCRT group these were 19 months, 44.1%, and 19.6%. Esophageal and constitutional toxicities were more pronounced in the CCRT group, while there was no significant difference in pulmonary toxicities. The results suggest that for unresectable stage III NSCLC, the outcomes of SCRT with accelerated hypofractionated radiotherapy and CCRT with standard radiotherapy are similar, but the toxicities associated with treatment are less in the SCRT group.