Two patients with chronic dissecting aneurysm (DeBakey type II) underwent graft replacement using open aortic technique. During proximal anastomosis, the body temperature of the patients was lowered to 23 degrees C and open distal anastomosis was performed under circulatory arrest of the lower body using selective perfusion to the brain. Graft-to-aorta anastomosis was performed in distal ascending aorta (case 1) and in aortic arch (case 2), after the approximation of inner and outer layer of the false lumen. Two patients survived operations, and the postoperative courses and postoperative angiograms were satisfactory. Open aortic technique was considered to be applied not only to patients with arch aneurysm or arch dissection but also to patients with DeBakey type II or type I dissection.