Retinal vascular complications following embolization of carotid artery branches have been occasionally reported. Since the result can be catastrophic and is often irreversible, all efforts to prevent this complication should be considered prior to the intervention. We report the occurrence of a branch retinal artery occlusion following embolization of a maxillary sinus tumor. Cerebral angiography pre- and post-embolization; pathology results from the excised tumor; fundoscopic, visual field, and fluorescein angiographic findings are reported. A combination of risk stratification and preoperative evaluation methods which might help in prevention of this serious complication are discussed.