<p>Benign teratoma of the thyroid is a unique entity with an incidence of approximately 6% in the head and neck region. Adult teratomas are usually malignant while the benign are seen in the paediatric population. Tumour replacing a territory of the thyroid or in direct continuity, or existence of a partially developed thyroid, is the unanimous criteria. Even if one is fulfilled, the entity is labelled as a teratoma of the thyroid. A CT scan will diagnose a teratoma by detecting large cystic lesions replacing the thyroid, with or without any solid/enhancing components. Lymphoid hyperplasia, lymphoma, cystic hygroma, and thyroglossal duct cyst are to be differentiated from a teratoma of the thyroid. Absence of fatty components or calcifications on imaging, necessitates further work up to exclude malignancy. A 66-year-old male was diagnosed as a mature cystic thyroid teratoma. on histopathology after surgical intervention. Preoperative FNAC was misleading and was suggestive of an epidermal inclusion cyst and while imaging, a unilateral colloid cyst.</p>