Iliac artery aneurysms are commonly associated with abdominal aortic aneurysms, and isolated Iliac artery aneurysms are rare. Isolated Iliac artery aneurysm is commonly asymptomatic at diagnosis, though it can present rupture or symptoms caused by pressure on adjacent organs (obstructive urinary symptoms). We here report a case of acute renal failure in a 82-year-old patient due to a mortal isolated iliac artery aneurysm.