We present a rare manifestation of a chronic mandibular wound with a traumatic diathesis. A 38-year-old male patient sought medical consultation because of painless swelling in the mandibular symphysis and mild paresthesia of the lower lip. He mentioned a history of physical trauma to the mandibular symphysis 12 months ago. The radiographic evaluation and CT scan showed gross destruction of bone leading to a well-defined radiolucent lesion without any sclerosing margins. The histological examination revealed numerous spindle-shaped fibroblasts arranged in a fascicular pattern and scattered multinucleated and mononuclear cells with bizarre nuclei throughout the lesion. Moderate nuclear pleomorphism was evident with few mitotic cells. The lesion was diagnosed as a malignant fibrous histiocytoma of storiform-pleomorphic type based on the previous descriptions. After surgical removal of the lesion and the adjacent tissues and reconstruction, the patient was referred to a radiotherapist for continuation of treatment. Despite this therapy, the lesion recurred after a year, and prior to the second operation, the patient died as a result of brain involvement.