Two cases of internal carotid aneurysms, trapped and bypassed, by means of radial artery grafts are discussed. Neither case has permanent neurological deficit possibly because of an adequate blood supply via the radial artery graft bypass. Although the radial artery graft has been in common use among cardiac surgeons, it is still rare in the neurosurgical field. The advantage of the radial artery is discussed with comparison to other graft materials such as the saphenous vein and the superficial temporal artery. In properly selected cases, the radial artery graft is useful in preventing the ischemic damage caused by an aneurysm being trapped at the main arterial trunk.