OBJECTIVE: Uterine papillary serous carcinoma (UPSC) is uncommon endometrial cancer, but clinically significant because of its poor prognosis. The aim of this study was to identify clinical and pathologic characteristics of patients with uterine papillary serous carcinoma and to evaluate the overall survival compared with endometrioid adenocarcinoma of uterus. METHODS: Twenty one patients with uterine papillary serous carcinoma and 332 patients with endometrioid adenocarcinoma who were surgically staged at the Asan medical Center between 1989 and 2004 were analyzed with review of clinical characteristics; pathologic findings, surgical stages, treatment modalities, prognosis and survival time from medical records and pathologic reports. RESULTS: In 21 patients with uterine papillary serous carcinoma, the median age at the time of diagnosis was 60.9 years (range, 38-81 years), which occurred in 18 postmenopausal women (85.7%) and usually presented with abnormal vaginal bleeding (75%). Obesity, diabetes, hypertension, or a history of hormone replace therapy, known as risk factors of endometrial cancer, were not so frequently associated. In 21 patients with uterine papillary serous carcinoma, there were 10 patients (47.6%) with stage I disease, 2 (9.5%) with stage II, 5 (23.8%) with stage III, and 4 (19.1%) with stage IV. The 3-year survival rate was 97.4% in endometrioid adenocarcinoma and 43.1% in uterine papillary serous carcinoma in all stages. Among 21 patients with uterine papillary serous carcinoma who had surgical staging, 3 patients received only operation and 9 patients received radiation therapy after surgery, 6 patients received chemotherapy and 3 patients received concurrent chemotherapy and radiation therapy. CONCLUSION: Patients with uterine papillary serous carcinoma showed a higher rate of abdominal metastasis and poor prognosis compared to patients of endometrioid adenocarcinoma. Therefore, complete surgical staging like in cases of ovarian cancer is vital in determining disease prognosis and vigorous adjuvant therapies are required.