Xanthogranulomatous pyelonephritis is an uncommon form of chronic aggressive infection of the kidney and surrounding tissues usually affecting middle aged women. It is rarely seen in childhood. We report the case of a female child with a history of fatigue, progressive anorexia, and fever in whom a diagnosis of pyelonephritis on a predisposing factor of lithiasis was suggested. After initial antibiotic treatment, nephrectomy was needed for an acute general deterioration. Pathology demonstrated xanthogranulomatous pyelonephritis.