Juvenile nasopharyngeal angiofibroma (JNA) is a rare and locally aggressive tumor that commonly presents with painless nasal obstruction and severe, recurrent epistaxis. In this case report, we describe the successful management of a Radkowski stage IIIA JNA with extensive arterial supply from the internal carotid artery (ICA). Transnasal direct puncture embolization using Onyx (Medtronic, Minneapolis, Minnesota) was employed to effectively devascularize the tumor, enabling radical surgical resection in a single piece via endonasal and transmaxillary endoscopic approaches. The patient did not require blood transfusion and was discharged without neurological impairment. The effectiveness of preoperative embolization as a treatment strategy for JNA is also discussed.