The aim of this study was to compare overall survival (OS), progression-free survival (PFS), and relapse patterns between different modalities of treatment for uterine papillary serous carcinoma (UPSC). A retrospective review of 124 patients with pathologically confirmed UPSC was performed, of whom, 97 patients were eligible for study. Postoperative treatment groups included adjuvant radiotherapy consisting of whole abdomen and a pelvic boost (abdominopelvic radiotherapy [APRT]) (55 patients), paclitaxel and carboplatin chemotherapy (CT) for six cycles followed by APRT (18 patients), CT only (5 patients), and 19 patients were observed without postoperative adjuvant therapy. Three-year OS was 81% and 63% for the CT followed by APRT and APRT alone, respectively (P= 0.11). After controlling for stage, the group treated with APRT alone had significantly decreased OS and PFS compared to the CT/APRT group (HR 3.6; 1.3-9.8; P= 0.01) and (HR 2.9; 95% CI 1.1-7.3; P= 0.03), respectively. Within the limitations of a retrospective study, the results of this study indicate that multimodality postoperative treatment with paclitaxel and a platinum-based CT followed by APRT may increase the survival of patients with UPSC. However, further prospective studies using these combined modalities are needed to confirm these findings.