Abstract： Objective To explore the efficacy of sevoflurane or propofol combined with remifentanil during the maintenance of general anesthesia in thyroid gland surgery.Methods Sixty patients underwent thyroid gland surgery were randomly divided into tow groups.Once the larynx mask was intubated, anesthesia was maintained with propofol(the effect site concentration was 2.5 ～3.5mg/L) and remifentanil(the effect site concentration was 4.5 ～5.5μg/L) by TCI technique in group P,but with sevoflurane(2％～4％) and remfentanil(the effect site concentration was 2.5 ～4.0g/L)in group S.The depth of anesthesia was measured by the A-line TM AEP Monitor which expressed as A-Line ARX Index TM(AAI).All patients' SBP,DBP and HR were recorded at eight time points: before induction time(T0) ,after induction but before larynx mask intubation time(T1) ,intubate larynx mask time(T2) ,cut skin time (T3), separate thyroid gland time (T4), cut thyroid gland time (T5), remove larynx mask time (T6) ,leave the operation room time(T7).The emergency time,the conscious of the patients after anesthesia and the side effects were also recorded.Results There were no significant differences between the groups with respect to age,gender,weight,the duration of operation,the emergency time and the conscious of the patients after anesthesia.SBP,DBP,HR of the patients in both groups showed no significant difference at T0,T1 ,T2, T3 (all P ＞ 0.05), but had significant difference at T4,T5,T6, T7 (all P ＜ 0.05).Compare with group P,the incidentce of restlessness, dizziness, drowsiness, rigor and pain was significantly lower in group S(all P ＜0.05).The incidentce of nausea,vomit and aspiration did not appear in both groups.Conclusion Both groups showed good anesthesia effects and the patients also emerged from anesthesia quickly.But the anesthesia maintained with sevoflurane and remifentanil could bring more stable hemodynamics and lower incidence rate of the side effects.