Sclerosing mucoepidermoid carcinoma with eosinophilia (SMECE) is a recently described carcinoma of the thyroid gland associated with Hashimoto's thyroiditis and considered to have a relatively indolent clinical course. We describe two patients with SMECE and its aspiration and exfoliative cytologic features. Patient 1 was a 39-year-old woman with a goiter for many years. Examination of the lobectomy specimen revealed SMECE associated with Hashimoto's disease; 4 months later a total thyroidectomy was performed, metastases were found in nine lymph nodes in the neck. Two years later, fine-needle aspiration biopsy (FNAB) of a paritracheal mass revealed recurrent tumor. After 2 more years, two pleural fluid samples contained metastatic carcinoma with eosinophils. Patient 2 was a 61-year-old man with thyromegaly and vocal cord paralysis. The FNAB revealed a poorly differentiated carcinoma. The subsequent thyroidectomy demonstrated SMECE. Two years later, an FNAB of a vertebral mass demonstrated metastatic mucoepidermoid carcinoma. In all specimens, malignant cells with definite glandular and squamoid differentiation were present in small cohesive aggregates; eosinophils associated with the tumor cells were present in all specimens.