Sarcomas represent 1-2% of all malignant renal tumors in adults, with an incidence that increases with advancing age. Renal sarcoma is less common, but more lethal than sarcoma of any other genitourinary site. The common signs and symptoms associated with renal sarcoma in adults include palpable mass, abdominal or flank pain and hematuria similar to those seen with large, rapidly growing renal cell carcinomas. Usually, radical nephrectomy remains the treatment of choice for these tumors, which exhibits an aggressive biological behavior and an unfavorable prognosis. We describe an unusual case of renal leiomyosarcoma that underwent nephron sparing surgery, in a 55-year-old white woman, who had a renal mass for 3 years. The size of the renal mass did not change during this period and no distant metastasis occurred. The patient is still alive without any symptoms of relapse.