Introduction: Arteriovenous malformations (AVMs) of the jaws are considered as an unusual disease. Depending on the blood flow, size, and affected site of the AVMs, they may lead to life-threatening complications with significant morbidity. Mandibular AVMs may produce a wide variety of clinical signs and symptoms, which can lead clinicians to misdiagnosis and potential hemorrhages during inadvertent dental extractions in nearby areas of undiagnosed lesions. Although the spontaneous regres- sion of an AVM had already been recognized in other human organs, the complete disappearance of a mandibular AVM is still considered a rare phenomenon. We aimed to report a clinical case of a spontaneously regressing mandibular AVM. Case description: Nine-year-old boy was referred for Oral Medicine Clinic (Orocentro/Piracicaba Dental School - University of Campinas, Brazil) for the evaluation of a "mandibular lesion", with an hemorrhagic event history after the inadvertent extraction of a deciduous molar (tooth number 75) associated with the lesion. Intraoral examination revealed an exophytic component with erythematous lesion in the left alveolar ridge, bleeding to light touch, flaccid, pulsatile, with absence of symptoms, and presented mobility grade II in tooth number 36. Both, intraosseous and gingival involvement were observed. Panoramic radiograph showed dif- fuse bone thinning in the left mandibular body involving tooth 36. Tomographic exam showed the presence of hypodense lesion in the left mandibular body of considerable dimensions. Considering the clinical characteristics, we formulated the diagnostic hypothesis of AVM. An arteriography without any embolization procedure was performed and confirmed the AVM diagnosis. A spontaneous regression of the AVM clinically and on imaging tests was observed after the arteriography. Twelve month follow up keeps the complete spontaneous regression of the intraoral exophytic component, complete clinical remission of the lesion and number 36 mobility grade I. Results and conclusion: Although, oral AVM is a rare event, it may mimic benign inflammatory processes and reactive lesions. Thus, dental extractions associated with atypical lesions should be avoided until a vascular component is ruled out. Spontaneous regression of an AVM is an extremely rare event, not yet described in a mandibular lesion. In con- clusion, we speculate that this rare case of a spontaneous regression of AVM could be due to the hemodynamic changes in the circulation and pressure of the lesion induced by the arteriographic exam.