Patients undergoing major oncological surgery for head and neck cancer (SHNC) have a particularly high risk of nosocomial infections.We aimed to identify risk factors for ventilator-associated pneumonia (VAP) in patients undergoing SHNC.The study included 465 patients who underwent SHNC between June 2011 and June 2014.The rate of VAP,risk factors for VAP,and biological aspects of VAP were retrospectively evaluated.The incidence of VAP was 19.6％ (n =95) in patients who required more than 48 h of mechanical ventilation.Staphylococcus (37.7％),Enterobacteriaceae (32.1％),Pseudomonas (20.8％),and Haemophilus (16.9％) were the major bacterial species that caused VAP.The independent risk factors for VAP were advanced age,current smoking status,chronic obstructive pulmonary disease,and a higher simplified acute physiology score system II upon admission.Tracheostomy was an independent protective factor for VAP.The median length of stay in the ICU for patients who did or did not develop VAP was 8.0 and 6.5 days,respectively (P =0.006).Mortality among patients who did or did not develop VAP was 16.8％ and 8.4％,respectively (P ＜ 0.001).The potential economic impact of VAP was high because of the significantly extended duration of ventilation.A predictive regression model was developed with a sensitivity of 95.3％ and a specificity of 69.4％.VAP is common in patients who are undergoing SHNC and who require more than 48 h of mechanical ventilation.Therefore,innovative preventive measures should be developed and applied in this high-risk population.