Hyperbaric oxygen therapy, the administration of 100% oxygen at pressures > 1 atm, is believed to promote wound healing by increasing angiogenesis and collagen synthesis. To our knowledge, this treatment modality has never been described in patients with tracheal radionecrosis. Here, we report the case of a 55-year-old man diagnosed with stage IIIB lung adenocarcinoma who was treated with chemotherapy and concomitant external intensity-modulated radiotherapy involving the left lung and mediastinum. Nine months later, he presented with neck pain, cough with mucopurulent sputum, and fever. A PET-CT scan revealed a fissure in the posterior wall of the left upper trachea. Flexible bronchoscopy showed a tracheal ulceration with a small left posterior wall fissure that extended into the mediastinum. To our knowledge, this is the first report in the literature that suggests that treatment with hyperbaric oxygen therapy, local debridement, and antibiotics is a feasible and successful management option for patients with complicated tracheal radionecrosis.