The present report describes a case of acute airway obstruction in a newborn caused by an expanding hemorrhagic macrocystic lymphatic malformation (LM), which was successfully treated with emergent decompression and interventional radiology-guided sclerotherapy. The use of sclerotherapy for macrocystic LMs has been well described for various indications. The urgent interventional treatment obviated the need for a tracheostomy. This case describes the rapid diagnosis and use of sclerotherapy in a large expanding macrocystic LM.