We experienced a female patient with intramural hematoma of the aorta. This patient had a severe anterior chest pain radiating to interscapular area with choking sensation. CT revealed a intramural hematoma of the thoracic aorta and a part of the abdominal aorta but there was no evidence of intimal tearing. We did the eme gency operation under hypothermic circulatory arrest and retrograde cerebral perfusion. Ascending aorta was replaced and coronary artery bypass graft was done because of intimal tearing of the ostium of right coronary artery. She was discharged without any significant complication. We reported this case with consideration about necessity of emergency operation for intramural hematoma of the thoracic aorta.