Background: Radiation therapy remains one of the most effective methods of treating stage IIA prostate cancer. Several retrospective studies have determined that external beam radiation therapy (EBRT) or brachytherapy (BT) are equivalent to prostatectomy for survival. Although a recent retrospective cohort study showed no significant difference in external and internal radiation when using a biochemical endpoint, there are few studies with a survival endpoint. To our knowledge, we are the largest retrospective analysis comparing EBRT and BT with a survival endpoint in stage IIA prostate cancer. Methods: Using the National Cancer Data Base, we analyzed 122,405 patients with stage IIA prostate cancer who underwent radiation therapy for treatment of the primary tumor between 2004-2013 and had sufficient survival data. Patients with previous hormone therapy or surgery were excluded. EBRT includes any form of external radiation. BT consists of any method of internal radiotherapy. Combination therapy (CT) refers to any combination of external and internal radiotherapies. Survival was determined by time of diagnosis to time of last contact or death. A Kaplan-Meier curve was constructed and pairwise comparisons were performed using the log-rank test. Results: The average ages for EBRT, BT, and CT are 69, 66, and 66, respectively. The average PSA scores were 12.1, 11.9 and 15.0 ng/ml. There was no difference in Charlson comorbidity index between groups, with an average score of less than 0.15. The average tumors in EBRT and BT were characterized as moderately differentiated, while CT was poorly differentiated. There was a significant difference in survival for EBRT vs BT (p<0.001) and EBRT vs CT (p<0.001). There was not a significant difference between patients treated with CT and BT alone (p=0.673). Conclusions: The method of radiotherapy used contributes to the survival of patients with stage IIA prostate cancer, with brachytherapy with or without EBRT having improved survival. Careful selection of the proper treatment regimen should be used.