Objectıve To investigate the clinical characteristics, prognosis, survival and diagnosis of high-grade primary renal leiomyosarcoma. Materıals and Methods From January 2003 to April 2013, 10 cases of high-grade primary renal leiomyosarcoma were retrospectively reviewed. We analyzed clinical manifestations, treatment and prognosis of our group and correlated to the literature. Results Ten cases (five male and five female patients; age range 43–77 years, mean=57±std d:12.3 ) were enrolled. The mean diameter of the tumor masses was 9.35±4.5 cm (range 3-18 cm). 40% of the patients were asymptomatic while the major symptom of 60% patients was lumbar pain. Nephrectomy was performed in 90% of patients. Partial nephrectomy surgery was preferred for only one patient. Pleomorphism and necrosis with high-grade, pink spindle cell cytoplasm were viewed in all patients. All patients were high-grade, pink spindle cell cytoplasm and pleomorfism and necrosis were observed in all. In an immunohistochemical examination, vimentin was seen in 100%, desmin in 90% and smooth muscle actin in 80% of the patients. CD117 was negative in all patients. All of the cases were followed-up, and the time of survival varied from 6 to 68 months (mean 23.9±std d:20.1). No patient received adjuvant CTx and/or RTx. Conclusıon High-grade primary renal leiomyosarcomas (LMSs) are rare and highly malignant and the prognosis is poor. Early diagnosis and radical nephrectomy can prolong the patient’s life. Surgery is the main treatment modality for renal (leiomyosarcoma) LMS.