This case report describes a rare case of an adenomatoid odontogenic tumor (AOT) arising in the mandibular third molar region of a 20-year-old female. The tumor was a well-circumscribed intraosseous lesion with an embedded tooth. Histologically, the induction of extensive globular calcification was evident in addition to the characteristic histological features of AOT. The present case lends support to the categorization of AOT as an odontogenic tumor consisting of a disorderly mixture of odontogenic epithelium and odontogenic ectomesenchyme with calcification.