OBJECTIVE: The purpose of this study was to investigate the clinicopathologic findings, treatment, and outcome of patients with endometrial stromal sarcoma (ESS) of the uterus. METHODS: This study retrospectively reviewed 8 patients with histologically proven stage I low-grade ESS of the uterus, at the Department of Obstetrics and Gynecology of Korea University Kuro Hospital, between May 1994 and July 2005, for clinical profiles and survival. The median follow-up was 79 months and ranged from 7 months to 131 months. RESULTS: The median age at the time of diagnosis was 43 years (range: 29-49 years). The common presenting symptoms were vaginal bleeding, lower abdominal pain and vaginal discharge. Four patients were treated with surgery followed by postoperative adjuvant chemotherapy, and four patients were treated with surgery alone. Recurrence was in one patient, and the site was the lung. The overall five-year survival rate of stage I low-grade ESS was 100%. Bilateral salpingo-oophorectomy and adjuvant chemotherapy did not significantly affect the survival of patients (p>0.05). CONCLUSION: The patients with stage I low-grade ESS have a very excellent prognosis. The role of bilateral salpingo-oophorectomy and adjuvant chemotherapy have not get been clearly defined and further studies, including prospective studies with larger numbers of patients, are needed.