Background: Patients with locally recurrent or newly diagnosed NSCLC after previous definitive radiotherapy (RT) or surgery pose a challenge in management. SBRT has been attempted as option of salvage treatment. The objective of this study is to report long-term outcome of SBRT in patients with recurrent or second primary NSCLC after previous local treatment. Methods: This single-institution retrospective study included patients with NSCLC who received thoracic SBRT for newly diagnosed or recurrent NSCLC. The primary and second endpoints were overall survival and radiation pneumonitis, respectively. Clinical factors analyzed included age, gender, race, tobacco history, respiratory/cardiovascular comorbidity, histology, modality of previous treatment, T stage, gross tumor volume (GTV), planning target volume (PTV), and prescription dose. Radiation pneumonitis was graded consistently per RTOG1106. Results: A total of 326 patients met the inclusion criteria, including 43, 40 and 243 patients with prior RT, surgery, and no prior treatment, respectively. The median follow-up was 59 (95% CI 48-68) months. The median survival were 23 (95% CI 15-31), 50 (95% CI 35-65), and 32 (95% CI 25-40) months, and the 5-year survival rates were 26.2%, 42.4%, and 24.7%, respectively (P= 0.077). In those treated with previous RT, there were no significant differences in overall survival between conventionally fractionated radiation therapy and SBRT (median survival 25.0 vs 13.4month, P= 0.280). In those treated with prior surgery, there was no significant difference in overall survival between pneumonectomy and lobectomy (56.0 vs 50.0 months, P= 0.576). The were significant differences in rates of grade 1+ (44.2%, 30.0%, 21.5%, P= 0.007), and 2+ RP (18.6%, 12.5%, 7.0%, P= 0.039), but no statistically significant differences in grade 3+ pneumonitis among these three groups. Conclusions: Salvage SBRT after previous radiation or surgery provides a chance of cure, with 5-year survival not significantly different from that of SBRT for newly diagnosed NSCLC, with significantly increased but acceptable risk of radiation pneumonitis.