Ameloblastic fibrosarcoma(AFS) is a rare malignant odontogenic tumor presented as painful swelling and intraosseous mass with occasional ulceration. The most frequent site is the mandible body. AFS of the jaw generally occurs in all ages($3{sim}83$ years old), with the average age of 27.3. AFS was associated with high local recurrence rate of 37% in the areas of gingiva, floor of mouth and neck. Although metastasis is not a special feature of this lesion, 20% have died within 3 months to 19 years, due to locally aggressive tumor growth. This report describes an ameloblastic fibrosarcoma occurring in the mandible of a twenty-five year old male. The tumor was treated by partial mandibulectomy and reconstructed with a fibular flap. The patient has shown no signs of recurrence or complications during 18 months postoperatively. In this study, we report our case with a review of literatures.