Vascular anomalies of the middle ear are extremely rare. The most common anomaly is a persistent stapedial artery. This artery is important clinically because of the risk of profuse bleeding during middle ear surgery. We describe a 26-year-old woman with a glomus tympanicum tumor. The blood supply to the tumor was from a persistent stapedial artery. A preoperative angiogram supported this finding by demonstrating a small vessel originating from the anterior branch of the middle meningeal artery as the major vascular supply to the tumor. To our knowledge, this is the first case report of a glomus tympanicum tumor vascularized by a persistent stapedial artery that was suggested by angiography and confirmed intraoperatively. To better understand this anomaly, we review the embryological development of the stapedial artery and discuss its clinical significance.