Uterine sarcomas are rare tumors of mesodermal origin. They constitute 2-6% of uterine malignancies. The three most common histologic variants of uterine sarcoma are leiomyosarcoma(LMS), malignant mixed mullerian tumors(MMMTs) of both homologous and heterologous type, and endometrial stromal sarcoma(ESS). Endometrial stromal tumors are divided into three types on the basis of mitotic activity, vascular invasion, and observed differences in prognosis: 1) endometrial stromal nodule, 2) low-grade endometrial stromal sarcoma, 3) high-grade or undifferentiated endemetrial stromal sarcoma. Lower-grade ESS is distinguished from high-grade ESS microscopically by a mitotic rate of less than 10 MF(mitotic figure)/10 HPF as well as clinically by a more protracted course. We have experienced a case of low grade endometrial stromal sarcoma of the uterus in a 39-years-old woman, which is presented with a review of literatures.