Aim: Thymomas are rare neoplasms. Complete surgical resection is the cornerstone of the treatment. The role of adjuvant radiotherapy (RT) in Masaoka stage II disease is controversial, but in more advanced stages and the role of radical RT in inoperable cases are clear. This study is conducted to evaluate local control, relapse free survival and overall survival rates in Masaoka stage II and III thymoma patients after adjuvant or radical RT. Materials and Methods: The medical records of thymoma patients who were treated and completed their RT course between January 2010 and August 2016 in a single center were evaluated retrospectively. Results: Twenty-two patients were available for analysis. Treatment planning was adjuvant in 18 patients and radical in 5 patients. Median age at diagnosis was 59 (50-62). Type of resection was R0 in all cases. The adjuvant RT dose was 50 Gy; radical RT dose was 60-66 Gy. The most common acute toxicity was grade 1 pneumonitis which was reported in 9 patients (39%). Grade 2 acute pneumonitis was experienced by 3 patients (13%), grade 2 acute esophagitis was experienced by 2 patients (9%). One patient had late grade 3 esophageal toxicity. Follow-up time ranged from 6 to 99 months, median 18 months, local control rate was 100%, relapse free survival (RFS) was 96%, cancer specific survival was 96%, 2 years overall survival (OS) was 83%. Conclusion: Although our results seem to be in concordance with the literature, longer follow-up is needed to be able to make a conclusion in terms of LC, RFS and OS, since thymoma has an indolent course with low relapse rate and long RFS.