A bilobulated mature cystic teratoma (MCT) at the left ovary measuring 6 cm in diameter fistulized to the left lower quadrant of the anterior abdominal wall, contralateral to McBurney's point. This is the first reported case of a MCT fistulized to the skin. Symptoms, if present, usually depend on the size of the teratoma. However, most patients with a MCT are asymptomatic. Complications such as rupture of the cyst capsule are quite rare. Moreover, complication of fistulization is highly infrequent.