To compare two methods of double-lumen end bronchial tube placement for thoracic surgery and to identify factors those provide a rational basis for placement method. Some cases are in need to use bronchoscopes procedure during the operations. Other types of separation tube are required to be (especially in children) introduced. Patients: We were performed randomly placement 160 patients who underwent to thoracic surgery in the 2012-2014 years method was the traditional approach of placing the endobronchial tube through the larynx and then advanced blindly into the left and right main stem bronchus, some patients were intubated under direct vision using the fiber optic bronchoscope.The patients ASA physical status were II and III patients (18-80 years old) scheduled for surgical procedures requiring elective right and left-sided endobronchial intubation then ventilated one lung. Methods: The clinical records of the 160 cases, who had double-lumen endotracheal tubes to place in National Cancer Center of Mongolia. Our cases placement right and left double lumen tube, then we are in patients during one lung anesthesia. All cases were performed high thoracic level epidural catheterization and put double lumen tube for central (jugulars internal) vena. Double-lumen endotracheal tubes are not meant for postoperative ventilation. Results: We are reporting 2012-2014 anesthesia and surgical departments at National Cancer Center. In our study involved all 160 open thoracic surgery cases with DLT. In study had anesthesia tidal volume 7.77+1.07 ml/kg, one lung volume 5.87+0.46 ml/kg (p<0.014), the women DLT size 35.43+2.25 Fr, deep 27.68+2.47 cm, the man DLT size 37,09+4.69 (p<0.093), deep 28.43+2.6 cm (p<0.004). During anesthesia monitored average SpO2-95.09% + 1.07in analyzed arterial blood average SaO2- 92.65%+ 5.69 (p<0.03). Discussion: In reports it shows that 80-90% of double lumen tube placement performed a collapsed lung in open
