Thyrolipomas are rare capsulated mass lesions containing fat and thyroid tissue. We herein report the case of a 60-year-old man who had goitre for 10 years, with rapid enlargement of the gland during the last several months before presentation. Sonography, scintigraphy, CT, MR imaging, and sonography-guided fine needle aspiration were performed. Sonography and scintigraphy revealed an unusual mass of the thyroid. The diagnosis of thyrolipoma was based on CT and MR imaging findings and fine needle aspiration cytology.