Extracranial internal carotid artery aneurysms (EICA) are rare. Incidence is <1% of all an arterial aneurysm. This aneurysm being rare but is important because it is associated with a high risk of neurological thromboembolic events, cranial nerve compression, and rupture. The causes of the EICA are congenital, trauma leading to the pseudoaneurysm, atherosclerosis, infections, and fibromuscular dysplasia. Here, we describe a case report of a 69-year-old female with progressive enlargement of the right neck mass accompanied by dyspnea on exertion. The patient had been diagnosed as right EICA and underwent the endovascular procedure as parent vessel occlusion 4 years ago. There was still enlargement of the size of the right neck mass and was causing troublesome to the patient. We performed selective embolization of the various feeders to the mass, but after this also, it was still enlarging. Three-dimensional reconstruction of the computed tomography scan showed fusiform dilatation of the right proximal EICA. We made the diagnosis of the thrombosed EICA and hence we planned to undergo surgical management. We performed removal of the intraluminal thrombus and ligation of the EICA. The size of the swelling decreased significantly.