Mature teratomas are rarely located in the posterior mediastinum, and most mature teratomas are asymptomatic. Teratoma rupture into the adjacent lung and esophagus is possible but considering the rare entity of posterior mediastinal teratomas and the perforation rate, it is extremely unusual. We report a case of ruptured mature cystic teratoma located in the posterior mediastinum, showing fistula formation to the adjacent lung and esophagus, which presented with hemoptysis.