Persistent primitive hypoglossal artery is a rare variant of intrauterine anastomosis between the carotid and basilar arteries, which may remain in adults. The presence of this artery in carotid artery atherosclerosis increases the risks for stroke in the carotid and basilar basins. Our clinical case illustrates successful carotid endarterectomy in the presence of an ipsilateral persistent primitive hypoglossal artery under cerebral oximetry control.