We describe five boys, all of whom presented with urinary tract infection or acquired urinary incontinence some years after surgery for a high anorectal malformation (ARM). All were found to have a posterior urethral diverticulum thought to represent the remains of the original rectourethral fistula accompanying the high rectal atresia. Excision of the diverticula resulted in complete relief of symptoms. The clinical features and radiological appearances of the diverticula are described. A urethral diverticulum is one treatable cause of urinary symptoms in children with high anorectal malformations, and should be considered when symptoms recur late after definitive surgical correction of the malformation.