Collision carcinoma is a merging of two original separated neoplasms. It is very rare in head and neck fields, especially in metastatic foci. The authors had experienced a case of collision carcinoma in a metastatic cervical lymph node derived from papillary adenocarcinoma of the thyroid gland and squamous cell carcinoma of the subglottic larynx. The patient was a laryngectomee. So we managed by ipsilateral radical neck dissection, total thyroidectomy and postoperative radiation therapy.