Purpose: To assess the effectiveness of ethanol embolization for the treatment of arteriovenous malformation (AVM), and the complications, if any, arising. Materials and Methods: Thirty-three patients with AVMs underwent 145 staged sessions of ethanol embolization. AVMs were located in an upper extremity (n=14), a lower extremity (n=10), the pelvis (n=7), the thorax (n=1), or the abdomen (n=1). Eighty-five transcatheter embolizations and 60 direct percutaneous puncture embolizations were performed, and seven patients underwent additional coil embolization of the dilated outflow vein. The therapeutic effectiveness of embolization was evaluated in terms of the extent to which an AVM was obliterated between baseline and the final angiogram. Complications were classified as minor or major. Results: In 13 patients (39%), AVMs were totally obliterated. In eitht patients (24%), more than 75% were obliterated; in three (9%), the proportion was 50-75%; and in four (12%), less than 50%. Five patients (15%), were not treated. The reasons for failure were the difficulty of approaching the nidus due to previous surgical ligation or coil embolization of the feeding artery, the subcutaneous location of an AVM, post-procedural infection, and massive bleeding during the follow-up period. Twenty-one minor complications such as focal skin necrosis or transient nerve palsy developed during 145 sessions of (an incidence of 14%), but these were relieved by conservative treatment. The five major complications arising (3%) were cerebral infarction, urinary tract infection, acute renal failure due to rhabdomyolysis, permanent median nerve palsy, and infection. Conclusion: Ethanol embolization by direct percutaneous puncture or using a transcatheter technique is an effective approach to the treatment of an AVM. However, to overcome the considerable number of complications arising, further investigation is required.