The Adenomatoid Odontogenic Tumor (AOT) is a rare, slow growing, benign, odontogenic epithelial tumor with characteristic clinical and histological features; which usually arise in the second or third decade. It is a tumor composed of odontogenic epithelium in a variety of histoarchitectural patterns which are embedded in a mature connective tissue stroma. It is mostly encountered in young patients with a greater predilection for females. Maxilla is the predilection site of occurrence, most commonly associated with an unerupted maxillary canine. It presents as a symptom-free lesion and is frequently discovered during routine radiographic examination. This case report describes an unusual case of 20 year old male with only a one month history of tumor in the anterior mandible. The tumor was a well circumscribed intraosseous lesion with an embedded tooth. Histological evidence of calcification was present. The present case lends support to the categorization of AOT as a mixed odontogenic tumor