The aneurysmal bone cyst is a rare, expansive, osteolytic, pseudocystic lesion with an unknown etiology. It usually affects long bones and the spine. Two to 5 % of cases have mandibular localization (between 75 and 100 % present on the mandible) accounting for 1 % of all mandibular cysts. Less than 200 cases have been reported in English and French literature.