The Montgomery T-tube is widely used to stent airway stenotic diseases. Conventional insertion methods can sometimes fail in the case of long-distance subglottic stenosis due to the flexibility of a T-tube made of silicon, which kinks when forced against resistance. Therefore, an alternative approach can assist in the insertion of an extra-long T-tube, especially when using a long proximal limb. We report herein the case of a patient with a large mediastinal tumor caused by neurofibromatosis type 1 in which airway obstruction was avoided through the use of a novel extra-long T-tube placement technique.