The ameloblastic fibrosarcoma is the malignant counterpart of the ameloblastic fibrosarcoma in which the mesenchymal element has become malignant. Clinically it frequently occurs in the 3rd and 4th decades, and more frequent in the mandible than in the maxilla. Radiographic features are apparent multilocular radiolucency with ill-defined border. The authors experienced two cases of ameloblastic fibrosarcoma of the mandible in a 26-year-old male and a 48-year-old female patients who suffered from pain and swelling on the affected area. And we discussed the clinical, radiological and histopathological features of this disease with a brief review of the literatures.