trachea stenosis. Microwave tissue coagulation (MTC) and diathermy (MD) therapy via bronchofiberscope were performed on 37 patients with severe trachea stenosis diseases at least two times. The effective rate immediately after treatment was 100% in all cases. After one month, the rate remained 100% in the patients with benign diseases, but it dropped to 67% in the patients with malignant tumors. We have demonstrated that the microwave thermotherapy via bronchofiberscope is an effective method to treat patients with benign trachea stenosis noninvasively. For cancer patients with trachea soakage and blockage, it can be performed to improve their life quality by alleviating their agonies.