Multiple primary tumors in the head and neck are not uncommon, however those in the thyroid and the larynx are known to be very rare. In most cases of multiple primary tumors involving the thyroid and the larynx, lesions are observed usually simultaneously and thyroid tumors are found incidentally during the laryngeal tumor surgery. In rare cases, thyroid tumors are found metachronously after radiation therapy of laryngeal cancer. The authors recently experienced a case of multiple primary tumor involving the thyroid and the larynx, in which thyroid papillary carcinoma was the index tumor and the laryngeal squamous carcinoma was the meatachronous second tumor. Both tumors showed aggressive local extension and regional nodal meatastasis with tumor collision in the same node. The patient died of recurrent or of residual squamous carcinoma shortly after main surgical treatment index thyroid cancer.