Objective To investigate the efficacy and safety of three-dimensional radiotherapy (3DRT) with concurrent chemotherapy for stage IV non-small-cell lung cancer (NSCLC). Methods A total of 198 eligible patients from 2008 to 2012 were enrolled as subjects. With an age ranging between 18 and 80 years and a Karnofsky Performance Status (KPS) score of 70 or more, those patients had no contraindication for radiotherapy and chemotherapy, and were newly diagnosed with stage IV NSCLC confirmed by histology or cytology, as well as limited metastatic disease (≤3 organs). Survival rates and acute toxicities in those patients were evaluated. Results The 3-year follow-up rate was 98.5% and the 3-year sample size was 165. The median overall survival (OS) and progression-free survival (PFS) were 13.0 months (95%CI,11.7-14.3 months) and 9.0 months (95%CI,7.7-10.3 months), respectively, while the 1-, 2-, and 3-year OS rates were 53.5%, 15.8%, and 9.2%, respectively. Multivariate analysis showed that a primary tumor volume smaller than 134 cm³, a stable or increased KPS score after treatment, and a radiation dose of 63 Gy or more were independent prognostic factors for longer survival time (P=0.008;P=0.010;P=0.014). The incidence rates of grade 3-4 neutropenia, thrombocytopenia, anemia, grade 3 radiation esophagitis, and grade 3 radiation pneumonitis were 37.9%, 10.1%, 6.9%, 2.5%, and 6.6%, respectively. The maincause of death was distant metastasis, and only 10% of the patients died of recurrence alone. Conclusions 3DRT with concurrent chemotherapy achieves satisfactory treatment outcomes with tolerable toxicities for stage IV NSCLC. Primary tumor volume, change in the KPS score after treatment, and radiation dose are independent prognostic factors for OS.Clinical Trial Registry Chinese Clinical Reistry,registration number:ChiCTRC10001026.