BackgroundRiedel's thyroiditis (RT) is a rare form of chronic thyroiditis, associated with fibroinflammatory process involving the thyroid and surrounding cervical tissues, leading to compressive symptoms.Case presentationWe present a case of RT in a 73-year-old female with dyspnoea caused by severe trachea compression. She had reported dyspnoea during physical stress, and had noticed a large mass on the front of the neck. Despite the combination of various imaging modalities, the thyroid mass was not differentiated from thyroid malignancy and other thyroid disorder. Total thyroidectomy and tracheotomy were performed. During surgery, the thyroid had severe adhesion to surrounding tissue and the pathology revealed RT.ConclusionsClinicians should be aware of RT. It is important to differentiate this condition from other thyroid disorders, especially malignant lesions. Thyroidectomy is indicated for patients with compressive symptoms, suspicious malignancy and failure of conservative management.