Most congenital masses of the mouth floor are cystic, irrespective of their origin. They may obstruct airway or digestive tract or may present other complications. Recognizing and treating these masses expeditiously is imperative. Choristoma is a mass of normal tissue in an abnormal location; they are classified according to the predominant epithelial lining. Few cases have been reported lined with gastric and respiratory epithelia within the same cyst. This case report presents a 5-month-old boy with an infected choristoma involving the floor of the mouth and its successful management.