Background <p>Ectopic thyroid tissue (ETT) is a rare congenital anomaly caused by the abnormal embryonic migration of thyroid tissue, leading to its presence outside its usual pretracheal location. This condition can lead to diagnostic challenges, especially when located within the airway, as it mimics other respiratory disorders such as asthma.</p> Case presentation <p>We report the case of a 69-year-old man with endotracheal ETT presenting with severe dyspnea, and the lesion was initially suspected to be malignant. The diagnosis of ETT was confirmed through bronchoscopy and histopathological examination. The patient underwent successful endoscopic interventional therapy, resulting in significant symptom improvement and complete resolution of the airway lesion.</p> Conclusion <p>Although rare, ETT should be considered in the differential diagnosis of unexplained respiratory symptoms to prevent misdiagnosis and permit effective, minimally invasive treatment options such as endoscopic resection, which can significantly improve patient outcomes.</p>