Objective. Ewing's sarcoma of the kidney is rare and is usually found in young adults. We present here a single case study of Ewing's sarcoma found in an elderly man. Material and methods. A 73-year-old man underwent routine surgery for hydrocoele of the testis. He developed urinary obstruction symptoms, and radiological examinations revealed a tumour in the right kidney. Results. Microscopical, immunohistochemical, and molecular pathological analysis of the tumour was consistent with Ewing's sarcoma. FISH showed rearrangement of chromosomes 22q12 (EWSR1). The patient subsequently underwent nephrectomy followed by 6 adjuvant chemotherapy cycles. Follow-up after 7 months shows no recurrence. Conclusion. This case report presents not only the rare finding of Ewing's sarcoma in the kidney, but also the occurrence of this tumour entity in an elderly patient. Treatment options for the different types of renal tumours are vastly different and the need for a correct diagnosis is, therefore, vital.