Due to modern methods, thyroid surgery is generally considered quite safe. However, post-thyroidectomy hematomas, although rare, can be life-threatening and unpredictable complications of thyroid surgery. Most postthyroidectomy hematomas occur within 24 hours of surgery, with delayed hematomas occurring after one post-operative week being exceedingly rare. Herein, we report a case of delayed post-thyroidectomy hematoma with respiratory distress occurring on the eighth post-operative day in a patient who was not taking anticoagulants and had no hematologic diseases. Although most bleeding occurs within 24 hours, caution should be used even in such patients who are considered low-risk.