Objectives This article focuses on massive epistaxis and pseudoaneurysm in patients with NPC after radiotherapy and discusses clinically relevant treatment strategies. Design Retrospective the medical data of NPC patients with massive epistaxis after radiotherapy and review the English literature over the past 10 years. Setting Otorhinolaryngology department in the First Affiliated Hospital of Nanchang University. Participants 21 patients with massive epistaxis after radiotherapy for NPC. Main outcome measures Characteristics and related causes of massive epistaxis or pseudoaneurysms were analyzed in terms of the clinical stage of NPC, course of radiotherapy, and affected artery. An analysis was performed on the methods of endovascular interventional treatment of such pseudoaneurysms. Results 19 cases were accompanied with bone destruction of the skull base; 13 cases were found tumor recurrence; 15 cases were in stage III or IV of NPC; 14 cases were combined with pseudoaneurysms. Analysis with the imaging of pseudoaneurysms, we found that the petrous ICA was the most predilection site. There were 11 out of 14 pseudoaneurysms had sentinel hemorrhage in the initial phase. All 14 pseudoaneurysm patients were underwent endovascular interventional therapy, but one died from hemorrhagic shock during the procedure. There were no rebleeding again among other patients. Conclusions Pseudoaneurysm could cause massive epistaxis with high mortality. The formation of a pseudoaneurysm was closely associated with a high carcinoma stage, re-radiotherapy, and local bone destruction and infection. Most cases had sentinel epistaxis. The imaging material prompted that pseudoaneurysm had a predisposition to the petrous part of the ICA, while the preferred therapy was endovascular embolization treatment. Key poits 1.Patients with massive epistaxis mean a single nasal bleeding volume exceeded 100 ml, or cumulative bleeding volume was more than 300 ml. 2.Patients who presented with active oronasal bleeding should be rapidly managed by nasal packing. 3.When there is hemorrhagic shock, patients should undergo endotracheal intubation and blood transfusion before being transferred to the otorhinolaryngology department. 4.CTA and DSA are recommended for patients with massive epistaxis associated with NPC after radiotherapy. 5.Interventional embolization is recommended to patients with pseudoaneurysm.