A 25-year-old woman was admitted because of frequent vomiting and headache which had lasted over one week. She had initially clear consciousness but slowly progressive mild headache and dysphoria. Emergency cranial CT revealed a 4 cm haematoma in the left cerebellar hemisphere. CT angiography showed a 2×2 cm nidus of an arteriovenous malformation (AVM) in the left hemisphere fed from the left posterior inferior cerebellar artery and draining into the inferior hemispheric vein. We performed a surgical resection of the AVM after decompression therapy to counteract the brain oedema. She recovered completely without any neurological deficits. This case recalls the importance of cooperation between diagnostic neuroradiology and neurosurgery in emergency, considering AVM, even if infrequent, among possible diseases.