We report a case of severe airway obstruction due to endotracheal fibrosarcoma in a 3-year-old boy. Successful tracheal resection and reconstruction was performed under extracorporeal membrane oxygenation support. A solid, elastic hard tumor with a smooth surface was attached by a tiny stalk structure to the membranous part of the lower trachea. Histological findings of the tumor were consistent with infantile fibrosarcoma, showing proliferation of spindle cells forming interlacing patterns.