Uterine carcinosarcomas are rare aggressive biphasic neoplasms. Because of its rarity, limited data are available on potential prognostic parameters. While several studies support that carcinomatous components predict outcomes, others do not. In this study, we evaluated the clinical and histopathologic features of 196 uterine carcinosarcomas to identify potential prognostic factors. Patients' ages ranged from 34 to 95 yr (median, 68 yr). Seventy-three (38%) patients experienced tumor recurrence during follow-up. Tumors ≥5 cm, outer half myometrial invasion, lymphovascular invasion, lymph node metastasis, advanced stage (International Federation of Gynecology and Obstetrics stages III-IV), sarcomatous component on recurrence, sarcoma dominance, and positive cytology were significantly associated with shorter disease-free interval (P<0.05). In addition, serous histology and rhabdomyoblastic differentiation was significantly associated with worse 3-yr overall survival. Our data supports that both carcinomatous and sarcomatous components play a role in tumor progression and survival of uterine carcinosarcoma patients, suggesting their equal importance in guiding management decisions.