Objectives: The aim of the study was to assess the efficacy of combined therapy (surgery plus radiotherapy) and reasons of treatment failure in patients with uterine sarcoma. Material and methods: The analyzed clinical material involved 95 patients with uterine sarcoma (US) treated in the Cracow Branch of the Center of Oncology between 1980 and 1999. The studied group consisted of 70 patients with leiomyosarcoma (LS) and 25 patients with endometrial stromal sarcoma (ESS). Seventy-three women were diagnosed with stage I and II and 22 with stage III and IVA US. All patients in this group underwent radical hysterectomy with salpingo-oophorectomy followed by postoperative irradiation consisting of vaginal brachytherapy and external beam radiotherapy of the small pelvic area. Results: Out of 95 patients in the tested group, 46 (48.4%) patients survived 5 years with no evidence of disease. In the group of early-stage US there were 60.3% 5-year disease-free survivals. None of 9 patients with stage IVA was cured. In 36 among 47 uncured patients (76.6%) distant metastases was found. Conclusion: Combined surgery plus radiotherapy treatment was effective therapy in patients with early-stage US, nevertheless, it was ineffective in the group with advanced US, as none of the 9 patients with grade IVA was cured. The basic cause of treatment failure in the LS group was the spread of malignancy, whereas in the ESS group – locoregional recurrence.