We describe a case of sinonasal glomangiopericytoma (GPC), a rare perivascular tumour accounting for less than 0.5% of sinonasal neoplasms, presenting with refractory unilateral epistaxis. An anticoagulated male in his 60s required admission, nasal packing and unilateral left internal maxillary artery embolisation to achieve haemostasis.Following stabilisation, nasoendoscopy identified a vascular polypoid lesion arising high in the left nasal cavity near the olfactory cleft. MRI demonstrated a contrast-enhancing mass abutting the cribriform plate without orbital or skull-base invasion, which had not been recognised on prior imaging. Endoscopic biopsy confirmed GPC, followed by endoscopic resection at a tertiary skull-base centre.Postoperative recovery was uncomplicated, with early resolution of epistaxis and safe recommencement of anticoagulation. However, the tumour was transected at the surgical margin, indicating incomplete or margin-uncertain excision and requiring close surveillance for residual or recurrent disease. This case highlights a rare cause of refractory unilateral epistaxis and illustrates the importance of diagnostic vigilance, multidisciplinary management and the potential role of embolisation in selected high-risk patients.