Aneurysms arising at locations other than arterial division are rare and the incidence of intraoperative bleeding is far higher in such aneurysms than in usual aneurysms. The authors report a case of intraoperative rupture and laceration on internal carotid artery(ICA) wall during dissecting a dorsal wall aneurysm on supraclinoid ICA and successful repair of the laceration on the parent ICA with microsuture and a Sundt clip-graft.