Fibrosarcomas are relatively uncommon malignant tumors arising from fibrous connective tissue and are characterized by increased abnormal proliferation of malignant fibroblast. Fibrosarcoma is capable of local recurrence and metastasis with poor prognosis. Approximately 0.05% of cases are noted in the head and neck region amongst all the cases recorded in the human race. In the present case, we report a case of fibrosarcoma of the mandible in 24 years old female who was presented with small intraoral swelling in the lower anterior vestibule with the involvement of floor of the mouth. Histopathology revealed a proliferation of malignant fibroblast cells arranged in a classical herringbone pattern.