Fibrosarcoma is a rare disease in larynx or hypopharynx. It is quite different from epidermoid carcinoma in the aspects of invasive behavior, metaststic route and treatment modality. The prognosis of this tumor is unfavorable because of high rate of local recurrence and distant metastasis, so wide surgical resection is generally recommended for the treatment of fibrosarcoma. The authors experienced a case of fibrosarcoma of laryngopharynx in a 17-year-old male patient which was treated by partial pharyngectomy.