Tracheal extubation is a critical stage and expensive practice in patients undergoing major operations such as liver transplantation. This study was carried out of determine factors affecting extubation time in liver transplant patients. From 2003 to 2006, all patients undergoing liver transplantation in Nemazee Hospital affiliated to Shiraz University of Medical Sciences entered our study. All patients were anesthetized identically and the time of extubation was based on standard protocol of extubation. The patients were divided into two groups of extubated after admission in less and more than six hours. The effect of 19 pre and post operative factors on extubation was also evaluated . Two hundred patients (Group 1=121; Group 2=79) entered the study. Twenty seven patients died in post operative course and 37 required reintubation among them, 14 were from the extubated group. A significant correlation was observed between amount of bleeding during operation, duration of surgery and blood pressure and the time of extubation. They early extubated group had significantly two days less stay in ICU. It seems that duration of surgery, bleeding during operation, and an abnormal blood pressure may delay the time of extubation. An early extubation may result into a decrease in duration of ICU admission.