ABSTRACTAdenomatoid odontogenic tumor (AOT) is a rare tumor comprising only 3% of all odontogenic tumors. It is a benign, encapsulated, noninvasive, nonaggressive, slowly growing odontogenic lesion associated with an impacted tooth. These lesions may go unnoticed for years. The usual treatment is enucleation and curettage, and the lesion does not recur. Here, we present a rare case of an unusually large aggressive AOT of maxilla associated with impacted third molar. The authors also discuss clinical, radiographic, histopathologic, and therapeutic features of the case. Subtotal maxillectomy with simultaneous reconstruction of the surgical defect with temporalis myofascial flap was planned and carried out.