OBJECTIVES: To report a new case of asymptomatic capsular leiomyoma. METHODS: 68-year-old male asymptomatic patient who was diagnosed of solid mass after a radiological study (ultrasound and CT scan). RESULTS: The treatment of this neoplasia was radical nephrectomy, with an uneventful postoperative course and a pathology report of renal leiomyoma. CONCLUSIONS: Renal leiomyoma is a rare benign mesenchymal tumor that should be taken into consideration for the differential diagnosis of renal masses, because it would be an indication for nephron-sparing surgery; never- theless, due to the difficulties to differentiate it from renal cell carcinoma it is not rare that the diagnosis is achieved after histological study of the nephrectomy specimen.