Epignathus is an extremely rare type of congenital teratoma arising in the oral cavity. Although it is a benign tumor, it is associated with high mortality and morbidity rates because of severe airway obstruction and other malformations. We present a case of epignathus affecting one fetus in a twin pregnancy. The tumor was associated with multiple congenital malformations including cleft palate, bifid tongue, bifid uvula, congenital heart defect, and bilateral inguinal hernias. The diagnostic value of three-dimensional ultrasonography and magnetic resonance imaging was explored with respect to antenatal counseling and peripartum management.