Castleman disease (CD) is an uncommon benign lymphoid hyperplasia with several clinical and morphologic variants associated with distinct outcomes. Pulmonary CD has been reported as a rare extranodal manifestation in the literature. However, CD presenting as an obstructive mass in the airway has not been documented. We report a case of localized hyaline-vascular CD presenting as an endotracheal lesion. The patient was a 50-year-old woman with Marfan syndrome. The lesion caused near-complete airway obstruction with respiratory insufficiency. The patient underwent laser resection, and the diagnosis of CD was supported by comprehensive studies including histopathologic, immunohistochemical, and molecular methods.