Abstract： Objective The aim of this study was to evaluate the safty and the efficacy of etomidate combined with propofol for gastroscopy.Methods In a double-blind study,300 patients undergoing gastroscopy were randomly allocated into 3 groups.Propofol was used in Group A; etomidate combined with propofol were used in Group B and etomidate was used in Group C.Heart rate (HR),non-invasive blood pressure (NIBP)and respiratory rate(RR)were monitored and recorded before anesthesia(T0),one minute after anesthesia(T1)and the time of recovery(T2).The gastroscopy time and recovery time were calculated.In addition,the incidence of intraoperative body movement,apnea,hypoxemia,bradycardia,hypotension,myoclonus,injection pain and postoperative complications were also recorded.Results Compared with propofol group,the awakening time in etomidate group was significantly reduced[(7.3 ± 1.3)min vs(9.1 ±2.0)min,P＜0.05].In propofol group,compared with T0,systolic blood pressure(SBP),diastolic blood pressure(DBP),HR and RR in T1 were decreased significantly [(94 ± 16)mm Hg vs (115 ±17)mm Hg,(51 ± 14)mm Hg vs (63 ± 16)mm Hg,(68 ±9)/min vs(78 ± 11)/min,(9.6 ±2.4)/min vs (18.5 ±3.1)/min,all P＜0.05].However,compared with T1,DBP,HR and RR in T2 were increased significantly[(57 ± 12)mm Hg vs (51 ± 14)mm Hg,(75 ±7)/min vs(68 ±9)/min,(13.9 ±2.6)/min vs (9.6 ±2.4)/ min,all P ＜0.05].Compared with T0,HR and RR in T1 were significantly decreased In etomidate combined with propofol group[(72 ±8)/min vs(79 ±9)/min,(14.9 ±2.7)/min vs (18.6 ±2.1)/min,all P＜0.05],compared with T2,HR was decreased in T1 while increased in T0[(72 ±8)/min vs (76 ±8)/min,(79 ±9)/min vs (76 ± 8)/min,all P ＜0.05].In etomidate group,SBP,DBP,HR and RR were not effected in T0,T1,T2(P ＞0.05).The number of adverse reaction cases in three groups were 89、71 and 68 respectively.Conclusion Etomidate combined with propofol can be safer and more effective than each of them used alone in painless gastroscopy.