Abstract: Objective: To investigate the effect of dexamthasone and droperidol in prevention of postoperative nausea and vomiting(PONV) after laparoscopic cholecystectomy(LC).Methods: One hundred and eighty ASA physical statusⅠor Ⅱpatients were randomized into three groups.Group A(n=60):Normal saline 10 ml was administered intra venous before surgery.Group B(n=60):dexamethasone 10 mg and Group C(test group,n=60):dexamethasone 10 mg and droperidol 20 μg/kg were administered intra venous before surgery.The occurrence of PONV was recorded and assessed during 48 h after the surgery.Results: The incidence of PONV in group A was 68.3%,group B and group C were 26.7% and 8.3% respectively.There were significant difference between group A and Group B,group A and group C,and Group B and group C(P<0.005).Conclusions: Dexamethasone and the low-dose droperidol is better than dexamethasone alone and placebo in prevention of PONV after LC.