A 15 years Old girl was admitted with chief complaints of intermittent claudication of lower extremity, dizziness, and headache for 5 years. On admission, malignant hypertension was noted in the upper part of body [190-150/120-110] but femoral & dorsalis pedis pulse could not palpate. Once she had experienced C. V. A. due to hypertension of upper part, about years ago. On auscultation, systolic murmur was audible along the left sternal border. E.C.G. Showed left ventricular hypertrophy pattern, and others within normal limit. Retrograde aortography demonstrated diffuse narrowing of entire thoracic aorta with underdeveloped lower abdominal aorta [below the renal artery] & both common lilac artery, and rich collaterals, but normally visualized greater arteries in the aortic arch. On left posterolasteral thoracotomy, entire descending thoracic aorta revealed marked narrowing with mild perivascular adhesion, but no mediastinal pleura adhesion. These findings suggest as congenital type of atypical coarctation in the entire thoracic aorta with mild secondary change. But histopathology was showed the findings of chronic non-specific aortitis, later. Dacron by pass graft was performed with end to side anastomosis between graft and aortic wall. After operation, all her preoperative symptoms & signs were disappeared, and discharged with good general condition.[KTCS 1978;1:81-84]