Spindle cell carcinomas of the head and neck are unusual neoplasms that are histologically biphasic, having both squamous cell carcinoma and apparently malignant spindle cell or sarcomatous element. Controversy about the histogenesis of these tumors has resulted in various terminology ; sarcomatoid carcinoma, pseudosarcoma, carcinosarcoma, and spindle cell carcinoma. The clinical course and natural history of these tumors are also variable. We report a case of 64-year-old male who complained of a neck mass. The patient was treated with extended radical neck dissection and postoperative radiotherapy, but the primary site of spindle cell carcinoma could not be found. We reviewed the clinical course, treatment, prognosis, and histogenesis of spindle cell carcinoma of the head and neck.