The arteriovenous malformation, an uncommon lesion, is a direct communication between an artery and a vein that bypasses the intervening capillary bed. The authors experienced two cases of arteriovenous malformation in 17-year-old and 18-year-old female patients who had suffered from mandibular pain and gingival bleeding. As a result of careful analysis of clinical and angiographic radiological examinations, we diagnosed them as arteriovenous malformations, and the results were as follows : 1. Main clinical symptoms were dull pain and gingival bleeding on the mandibular body area, and reddness, pain on palpation, thrill and palpitation in the lesional sites were also observed. 2. Radiographically, well-defined radiolucent lesions with multiple osteolytic defects were observed. In radio-nuclide scan, increased uptakes of radioisotope were observed in the lesional sites. 3. Increased venous shunt supplied by the facial, lingual and inferior alveolar arteries was observed in angiography. After embolotherapy was performed, no recurrence was reported during 3 to 6 months follow up.