Eight cases treated with Nd-YAG laser via fiberoptic bronchoscopy were studied. Four of them were primary lung cancer, one was tracheal invasion of thyroid cancer and three were postintubation lesions of trachea. In six cases, Nd-YAG laser treatment was effective for enlargement of the airway lumen and improvement of their symptoms. In the cases of advanced lung cancer, not only local findings of the tumor but also clinical stage and possibility of adjuvant therapy must be considered to apply this procedure. In the cases of postintubation tracheal stenosis (except polypoid lesions), T-tube stenting or surgical reconstruction must be followed after laser treatment. Nd-YAG laser treatment can be useful for the tracheobronchial lesions such as primary tracheal tumors, lung cancer, metastatic tumors, postintubation tracheal stenosis and so on if applied precisely.