Multimodal prophylaxis for postoperative nausea and vomiting (PONV) has been rec-ommended, even in low-risk patients. Midazolam is known to have antiemetic properties. We researched the effects of adding midazolam to the dual prophylaxis of ondansetron and dexam-ethasone on PONV after gynecologic laparoscopy. In this prospective, randomized, double-blinded trial, 144 patients undergoing gynecological laparoscopic surgery under sevoflurane anesthesia were randomized to receive either normal saline (control group, n = 72) or midazolam 0.05 mg/kg (mida-zolam group, n = 72) intravenously at pre-induction. All patients were administered dexamethasone 4 mg at induction and ondansetron 4 mg at the completion of the laparoscopy, intravenously. The primary outcome was the incidence of complete response, which implied the absence of PONV without rescue antiemetic requirement until 24 h post-surgery. The complete response during the 24 h following laparoscopy was similar between the two groups: 41 patients (59%) in the control group and 48 patients (72%) in the midazolam group (p = 0.11). The incidence of nausea, severe nausea, retching/vomiting, and administration of rescue antiemetic was comparable between the two groups. The addition of 0.05 mg/kg midazolam at pre-induction to the dual prophylaxis had no additive preventive effect on PONV after gynecologic laparoscopy.