Carcinoma ex pleomorphic adenoma (CXPA) is defined as a malignant salivary gland tumor arising from a primary or recurrent pleomorphic adenoma. Only three cases of CXPA of the trachea have been reported in the literature.We report a case of tracheal CXPA in a 55-year-old woman, who presented with a more than 3-mo history of progressive dyspnea. Computed tomography of the neck and thorax revealed an inhomogeneous, broad-based lesion arising from the tracheal wall on the right side. Endoscopy revealed a subglottic neoplasm causing up to 90% luminal stenosis. The tumor was resected using a high-frequency electrosurgical snare combined with argon plasma coagulation. Histopathology and immunohistochemistry revealed that the tumor was a CXPA of the trachea.We report the fourth case of tracheal CXPA, and present the first instance of resection of CXPA using high-frequency electrosurgical snare and laser ablation. We also discuss the pathogenesis, diagnosis, histopathology, and systemic therapy of this rare disease.