Abstract: Objective To investigate the effect of preoperative intranasal dexmedetomidine on postoperative emergency agitation after pediatric inhalation combined with anesthesia.Methods Sixty children aged 2-6 years who underwent open inguinal hernia repair from April to December 2018, were randomly divided into two groups：D group（dexmedetomidine 1μg/kg group）and C group (saline 0.6ml control group)，with 30 cases in each group. 1 μg/kg dexmedetomidine were given in D group , and 0.6ml saline nasal drops were given in C group. All children were accompanied by the parents in the anesthesia preparation room, after 35 minutes all children enter the operating room. Separation score from parents and mask induction quality score were recorded，MAP and HR were recorded during child entering the room (T1)，after tracheal intubation(T2), when the skin was cut (T3), When removing the laryngeal mask (T4). PAED scores and FLACC scores were recorded at eye—opening immediate (T5), after eye—opening 5 min (T6), 10 min (T7), 15 min (T8), 30 min (T9). The operation time, recovery time, and PACU stay time , adverse events (such as throat, bradycardia, nausea and vomiting) were recorded; Results The preoperative sedation satisfaction rate and mask inhalation induction cooperation satisfaction rate in D group were higher than that in group C (P<0.05). The mean arterial pressure and heart rate in group D were lower than those in group C (P<0.05). The incidence of postoperative agitation in group D was lower than that in group C (3.3% VS 53.3%，P<0.05). The PAED scores and FLACC scores in group D were significantly lower than that in group C (P<0.05). There was no significant difference in operation time, recovery time , PACU stay time and the incidence of adverse events between the two groups (P>0.05). (P>0.05).Conclusion Preoperative intranasal dexmedetomidine can reduce the incidence of emergency agitation during the recovery period, reduce the preoperative anxiety of children effectively and have a slight impact on hemodynamics.