Ewing sarcoma/primitive neuroectodermal tumor (PNET) is a high-grade malignant neoplasm commonly affecting bones of the thoracic region. Primary Ewing sarcoma/PNET of the kidney is exceptional; it commonly affects young adults and is rarely reported in children.

Here we describe a case of renal PNET in a 10-year-old girl who presented at our institute with haematuria and abdominal lump. Computer tomography scan revealed a huge mass in the right kidney. Computer tomography-guided aspiration from the mass showed cytomorphological features of a small blue round cell tumor. The patient underwent right radical nephrectomy. Histopathology with supplementary immunohistochemistry confirmed the diagnosis of PNET. She has been receiving treatment with adjuvant chemotherapy post-surgery and is currently disease free.

Primary renal PNET is a distinct and rare entity. This tumor is very aggressive with low survival rate, even with a multi-disciplinary approach. We reported the case because it is rare in children, poses diagnostic challenges, is aggressive in behaviour and responds poorly to treatment.