Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is a recently recognized malignant neoplasm of the thyroid gland. About 14 cases of SMECE have been reported and this is the first reported case in Korea. A 57-year-old woman presented with right neck mass for 20 years. Total thyroidectomy was performed under the impression of thyroid carcinoma. The resected thyroid gland showed a poorly circumscribed hard mass. Histologically, the tumor consisted of solid nests of large atypical cells with dense fibrous stroma. The tumor cells showed squamoid appearance with abundant eosinophilic cytoplasm. There were also rare mucin-containing cells within the nests. Within the hyalinized stroma, numerous eosinophils were found. The surrounding thyroid parenchyma displayed Hashimoto's thyroiditis. There was metastasis in a regional lymph node. Two years after initial surgery, she underwent a modified radical neck dissection due to recurrent neck mass. After the radiation therapy for eight weeks, laryngectomy and esophagectomy were performed due to a recurrent carcinoma in the esophageal wall. We report an additional case of SMECE, with metastasis to regional lymph nodes and esophagus. The tumor appears to be more aggressive than previously reported and a correct diagnosis can be rendered by just examining the metastatic lesions.