Papillary carcinoma is the most common malignant tumor of the thyroid gland, and it only infrequently invades the upper aerodigestive tract. When such invasion does occur, it is a source of significant morbidity as well as mortality. Although most thyroid tumors first clinically manifest as a neck mass, there have been few reports of patients whose initial compliant was a disturbance of the aerodigestive tract. The patient in our present study had no significant past medical history, and esophagoscopy and biopsy revealed papillary adenocarcinoma. We report here on a case of thyroid papillary carcinoma that was diagnosed by esophagoscopic biopsy. (Korean J Gastrointest Endosc 2009;38:339-342)