The occurrence of rectal diverticula are rare. They are invariably accompanied by colonic diverticulosis, especially the sigmoid segment. To our knowledge, this condition has not been previously detected during childhood, and the youngest patient reported was 18 years old. In this report we present a solitary rectal diverticulum in a 25-day-old infant without accompanying colonic diverticula. The existence of rectal diverticulum in this infant convincingly suggests a congenital etiology.