Primary renal osteosarcoma is an uncommon tumor type. To our knowledge, only 18 such cases have been reported to date. This tumor is very aggressive and may be localized or distant, the survival rate being less than 18 months despite a radical surgical procedure. Polichemotherapy has been attempted. We report on a 47-year-old patient with primary osteosarcoma of the right kidney, 8 cm x 8 cm in diameter, which was not amenable to surgical excision due to invasion of the adjacent structures. Systemic polichemotherapy was unsuccessful, and the patient died 3 months following diagnosis with multiple pulmonary metastases.