OBJECTIVE： To explore the preventive effects of dexmedetomidine on postoperative agitation of pediatric sevoflurane general anesthesia. METHODS： 41 children underwent amygdalectomy/adenoidectomy of general anesthesia were selected and randomly divided into SD group （21 cases） and SN group （20 cases）. Both groups received atropine 0.01 mg/kg， cisatracurium 0.15 mg/kg and 8％ sevoflurane to induce anesthesia. After intubation， the lungs were clear and equivalent to auscultation bilaterally， and then both groups received mechanical ventilation and intravenous pump of remifentanil 0.15 μg/（kg·min）. After the operation began， SD group was given dexmedetomidine 0.5 μg/（kg·h）and SN group given normal saline 0.5 μg/（kg·h）via intravenous pump. At the end of operation， anesthetics was discontinued； the children respired autonomously， tidal volume retune to normal， and deglutition reflex and cough reflex recovered； an then the tube could be drawn. Heart rate （HR） and mean arterial pressure （MAP） of 2 groups were recorded before intravenous pump of dexmedetomidine （T1）， at 10 （T2）， 20 （T3）， 30 min （T4） after intravenous pump， at the moment of extubation （T5）. Postoperative extubation time and opening eyes， the occurrence of ADR were observed in 2 groups. The degree of postoperative agitation and pain （CHIPPS score） were scored in 2 groups. RESULTS： Compared with before treatment， MAP and HR of SD group were decreased at different time points after treatment

but no change was found in SN group; there were statistical significance in MAP and HR between 2 groups at T2-T5 （P＜0.05）. Postoperative extubation time and opening eyes time of SD group were significantly longer than those of SN group， while agitation score immediately after operation， the incidence of agitation and CHIPPS score were significantly lower than SN group， with statistical significance （P＜0.05）. No obvious ADR was found in 2 groups. CONCLUSIONS： For pediatric amygdalectomy/adenoidectomy， dexmedetomidine as adjunctive drug of general anesthesia prolongs the time of postoperative extubation and opening eyes， but can effectively reduce postoperative agitation score， the incidence of agitation and CHIPPS score. It helps the children to feel more comfortable during anesthesia recovery period.