Purposes: To report the outcomes and patterns of failure of Stage III endometrial carcinoma. Materials and Methods: Medical records of Stage III endometrial carcinoma patients were retrospectively reviewed. Disease-free survival (DFS) and patterns of failure were reported. Factors to predict pelvic and extra-pelvic recurrences were described. Results: Seventy-nine patients with Stage III endometrial carcinoma were included. Most had Stage IIIA (53%) and IIIC disease (33%) with endometrioid cell types (73%). Fifty-five percent of patients received chemotherapy (CMT) alone, 25% received external beam radiation therapy (ERT) alone, 20% received a combination of CMT and ERT. Median follow up time was 47 months. The two-year DFS rate was 78.5%. Pelvic and extra-pelvic recurrences were found in 6.3% and 15.2%, respectively. Major pattern of failure for Stage IIIA was pelvic recurrences, whereas most of Stage IIIC disease failed at the extra-pelvic sites. Conclusion: Adjuvant CMT is essential, especially in Stage IIIC disease. Pelvic lymph node dissection appeared to be a significant prognostic factor for pelvic recurrence. Stage IIIC disease, lymphovascular space invasion, gross residual disease after surgery, received ERT alone or sequential CMT/ERT was found to be factor to predict extra-pelvic recurrences.