Fetal urinary ascites is usually secondary to an obstructive uropathy or neurogenic bladder. We present such a case in the absence of these conditions, but the presence of ipsilateral vesicoureteral reflux with Hutch diverticula. The patient was a 5-day-old boy presenting with distension of the abdomen and impairment of renal function. Tests revealed urinary ascites and renal insufficiency which spontaneously resolved after transurethral urinary drainage was established. This rare complication should be considered in neonates with high intrapelviureteric and intrarenal pressure as a result of high-grade vesicoureteral reflux with paraureteral diverticula. (C) 2008 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.