Objectives: To evaluate effectiveness of applying surgical excision posterior 1/3 of unilateral vocal cords using ultrasound knife via endoscopy in treatment of bilateral vocal cord paralysis. Method: With 16 patients of bilateral vocal cord paralysis. a clinical interventional study was carried out from 2011- 2014 in Gia Dinh people's Hospital. Result- Discussion: From 2011 to 2014, with the 16 patients bilateral vocal cord paralysis study, the authors had a follow-up after surgery at 1 month, 3 months, 6 months, 1 year. Evaluation results according to subjective and objective criteria: 100 percent cases improve airway, no cases of recurrent dyspnea, patients with hoarseness after surgery showed improvement after speech therapy. Conclusion: Results of Surgical excision posterior 1/3 of unilateral vocal cords using ultrasound knife via endoscopy improved airway for patients of bilateral vocal cord paralysis with safety, shorten hospital stays, helped to solve dyspnea but still preserved speech and swallowing function. Patients satisfy with the surgical results.