Fibrosarcoma is a sarcoma in which the cells tend to differentiate into fibroblasts, producing reticular fibers and collagen fibers. Fibrosarcoma is relatively common in oral and maxillofacial sarcomas and is a malignant tumor derived from fibroblasts in the oral and facial area. It can occur in connective tissues within the periosteum of the jawbone, periodontal membrane, and oral soft tissues, such as the lips, cheeks, tongue, and occasionally within the jawbone. It is most common in the anterior symphysis of the mandible, the mandibular angle, and condyle, and also occurs in the posterior part of the maxilla and maxillary sinus. Fibrosarcoma within the jawbone is more common in children and young adults; fibrosarcoma of the oral soft tissues is more common in middle-aged and壮年 people, and its malignancy depends on the degree of cell differentiation and growth rate.