Abstract: Objective To explore the impact of different timing of oral care on nursing efficacy of ventilator-associated pneumonia.Methods A total of 129 critically ill patients during mechanical ventilation were randomly divided into group A,group B and control group,with 40 cases per group.The control group was treated with routine oral care every 12 h,A group for eight hours,group B for five hours.Early,delayed and overall incidence of VAP were compared in three groups,VAP occurrence time,the incidence of oral complications were observed,and mechanical ventilation,length of hospital stay and mortality were compared.Results After nursing intervention,early,delayed and overall incidence of VAP of group A and group B were significantly lower than that of the control group (P ＜ 0.05),but VAP time between A group and B showed no significant differences (P ＞ 0.05);The occurrence of complications in A group were significantly better than that of the control group(P ＜0.05).Duration of mechanical ventilation,length of stay and mortality of B group were shorter than A group and control group (P ＜ 0.05),above three indicators of group A were significantly lower than that of the control group (P ＜ 0.05).Conclusion Effects of oral care timing of ventilator-associated pneumonia care are different,the three nursing methods can shorten oral care cycle time,significantly improve nursing effect of ventilator-associated pneumonia,but 5 h oral care has the best nursing efficacy,and it is worthy of clinical practice.