A case of Annuloaortic Ectasia associated with Marfan syndrome was treated by replacement of aorta and aortic valve with a valved conduit. A 26 years old man had suffered from palpitation and precordial pain. He had stigmata of Marfan`s syndrome. Aortogram and 2-D echocardiogram confirmed aneurysm of the ascending aorta with aortic insufficiency. Surgery was performed under the moderate hypothermia to 28oC. There was marked dilatation of the aortic annulus as well as sinus of Valsalva, with displacement of the coronary ostia. Aortic valve and aneurysm was replacement with 25mm, woven Dacron tubular graft, to which a 25mm, S.T. Jude Medical valve had been previously sutured. Right & left coronary ostia were anastomosed to the graft with the use of 3O Nylon pledget suture. The patient had a satisfactory post operation period with out specific complication.