Abstract We investigated the incidence of the trigeminocardiac reflex (TCR) during ethylene vinyl alcohol copolymer (Onyx Liquid Embolic System, ev3 Neurovascular, Irvine, CA, USA) embolisation of intracranial dural arteriovenous fistulas (DAVFs) and evaluated the post-procedural recovery of these patients. Between June 2006 and July 2009, 21 patients (11 females, 10 males) with a mean age of 61 years (range: 25–85 years) underwent 28 Onyx embolisations of intracranial DAVFs at our institution. The case histories of these patients were reviewed retrospectively. A TCR occurred in three (10.7%) of the embolisations, with bradycardia lower than 60 beats/minute and a drop in mean arterial blood pressure of 20% or more. The reflex was blunted promptly with intravenous atropine, and follow-up of these patients showed no complications that might have been directly related to it. The TCR may occur during Onyx embolisation of intracranial DAVFs. Recognition of this phenomenon allows for early detection and appropriate intraoperative management.