The trigeminocardiac reflex (TCR) consists of the sudden development of severe bradycardia or even asystole with arterial hypotension during manipulation of branches of the trigeminal nerve. TCR can occur during craniofacial surgery, rhizolysis of the trigeminal ganglion, and tumour resection in the cerebellopontine angle. We report a case of TCR-induced asystole during skin flap elevation in a patient undergoing craniotomy for cerebral aneurysm clipping.