A case of mandibular arteriovenous malformation (AVM) is presented.Prompt diagnosis and appropriate management are essential due to massive bleeding or even death after dental extraction or diopsy.

• 摘要下颚的动静脉畸型的速正确诊断及适当的治疗甚为重要，因拔牙或作切片检查时会造成大量出血甚至死亡。