Medullary thyroid carcinoma (MTC) is a rare calcitonin producing neuroendocrine tumour which arises from the parafollicular or C cells of the gland. The cytological diagnosis of MTC is often difficult due to varied cytological features, however it is associated with specific diagnostic markers. We report here a case of MTC. The diagnosis was made on fine-needle aspiration cytology (FNAC) and confirmed by histopathology, immunohistochemistry and special stain.