A moderately differentiated neuroendocrine carcinoma of the larynx is described. Although the patient had normal serum calcitonin level 36 months before, its level was elevated at the time the neck node was removed. This study supports the hypothesis that a diagnosis of calcitonin-producing neuro-endocrine tumor of the larynx with increased plasma calcitonin is possible and should be considered to avoid unnecessary thyroidectomy.