Bilateral vocal cord paralysis can result in severe airway compromise. Over the years a variety of arytenoidectomy procedures have bee described, and one or more of these have been the gold standard for many years. A widely accepted treatment is endoscopic laser total arytenoidectomy. However, vocal results are usually poor. Objective : To evaluate the effect of treatment of endoscopic laser medial partial arytenoidectorny for bilateral vocal cord paralysis Material and Methods : We performed endoscopic medial partial arytenoidceomy with $CO_2$laser for 3 patients with bilateral vocal cord paralysis. The $CO_2$laser is operated with a continuous 7-watt beam in superpulse mode. We compared degree of dyspnea and glottic area of pre-operation with those of post-operation for 3 patients. We analysed aerodynamic study pre-operatively and post-operatively for 1 patient. Results The symptom of dyspnea was improved markedly and the glottic area was widened from 34% to 50% compared with that of pre-operation. The voice quality was slightly decreased. Tracheotomy was not necessary for not-tracheotomized patient and decanulation was possible for tracheotomized patient post-operatively. Cunclusion： The endoscopic laser medial partial arytenoidectomy is a convient and effective method for opening the posterior glottic airway.