We describe open exposure of the inferior gluteal artery to allow coil embolization on an enlarging internal iliac artery aneurysm after previous abdominal aortic aneurysm (AAA) repair. An 84-year-old man with a stoma had undergone open AAA repair surgery 8 years previously, during which the proximal aortic neck and both proximal external iliac arteries were ligated, followed by an aorta to right external iliac and left common femoral bypass. Eight years later, he complained of abdominal pain, and a computed tomographic (CT) scan revealed persistent flow in the right internal iliac artery with enlargement to 8 cm in diameter. Because prograde access to the internal iliac artery was not possible as a result of the previous exclusion, the inferior gluteal artery was exposed surgically. Coil embolization of the arteries supplying the internal iliac artery aneurysm was successfully performed. The AAA and internal iliac artery aneurysm were treated by the exclusion technique. Eight years after the operation, CT revealed that the iliac artery had expanded to approximately 8 cm in diameter. The patient was placed face down, and a catheter was directly inserted into the internal iliac artery from the inferior gluteal artery. Four embolization coils were placed in the internal iliac artery and its branches. Absence of blood flow and shrinkage of the aneurysm were subsequently confirmed in the aneurysm, as shown by echogram color duplex scanning and CT scanning at 1 year. This technique could also be applicable for persistent blood flow in an internal iliac aneurysm after endovascular AAA repair, and the size of the aneurysm was reduced to approximately 1 cm 1 year after the operation.