About 40-85% of severe sepsis/septic shock patients developed acute respiratory failure, required endotracheal intubation. According to the nature of patients population, usually eldery, multiple co-morbid condition and high APACHE II score, sepsis patients were considerred as high risk for reintubation, after extubated. There was no information about HFNC versus NIV in prevention of reintubation among severe sepsis or septic shock patients.