This report describes the case of a 60-year-old man, who developed a giant punch-hole aneurysm of the ascending aorta five month after uncomplicated coronary artery bypass grafting (CABG) due to a localized rupture of the ascending aorta. The patient underwent surgical repair with cardiopulmonary bypass. Because the false aneurysm was adherent to the sternum, resternotomy was performed in deep hypothermia and circulatory arrest. The lesion in the ascending aorta was closed by means of a dacron-patch. The postoperative course of the patient was completely uneventful. We recommend to repair a false aneurysm of the ascending aorta in deep hypothermic circulatory arrest (DHCA) in order to avoid excessive blood loss during sternotomy.