A 39-year-old man presented with acute headache and neck pain, followed by quadriparesis and quadriparesthesia, accompanied by urinary and bowel incontinence. Lumbar puncture showed subarachnoid haemorrhage. Angiogram via a right axillary approach revealed severe coarctation of the aorta, between the left common carotid artery and left subclavian artery. Multiple collateral circulation including an enlarged anterior spinal arterial axis bridging the stenosed arch provided collateral circulation to the abdominal aorta. A small lobulated aneurysm was seen at the radiculomedullary-anterior spinal artery junction from the right ascending cervical artery. This patient underwent successful surgical clipping of the aneurysm. Pathogenesis of the spinal arterial aneurysm associated with coarctation of the aorta is likely to result from the haemodynamic stress from collateral circulation through the anterior spinal axis rather than segmental arterial disease or angiodysplastic disease. Aneurysms of the spinal artery are rare but can be unusually found in association with SCAVMs, coarctation of aorta, Klippel-Trenaunay syndrome or more rarely with aortic arch interruption.