Squamous carcinomas of the thyroid gland are extremely rare, and its clinical course is very aggressive. It has poor prognosis, similar to that of anaplastic carcinoma. These tumors are radioresistant and often rapidly fatal. It is considered to originate from the follicular epithelium at present. Recently, authors had experienced 63-years old female patient, proved to be primary squamous cell carcinoma of the thyroid. We report this patient with a review of a literature.