The technique of direct intratumoral injection of permanent liquid agents has evolved significantly over the past few decades. The percutaneous direct puncture technique is being utilised more and more for embolisation of head and neck hypervascular lesions. We describe a case treated via the direct percutaneous transnasal (TN) puncture technique for embolisation of a sinonasal hypervascular tumour, performed in a 21-year-old male patient. Due to extensive vascularisation of the tumour, preoperative embolisation was requested by our otolaryngologist team in order to minimise intraoperative bleeding and reduce surgical morbidity. A primary attempt at trans-arterial embolisation through selective ophthalmic artery catheterisation was unsuccessful due to unfavourable anatomy. An extensive devascularisation of the nasal fossa lesion was obtained using a single injection of low-density polymeric embolic agent (SQUID®). Post-operative eradication was uneventful. Final histopathology exam revealed vascular tumour consistent with a rare sinonasal glomangiopericytoma. To our knowledge, this is the first reported case of a rare sinonasal glomangiopericytoma treated by direct TN injection, utilising the liquid polymer agent SQUID®.