BACKGROUND: Selective 5-hydroxytryptamine type 3 (5-HT3) receptor antagonists are reported to have potent antiemetic effects for postoperative nausea and vomiting (PONV). The purpose of this study was to prospectively evaluate the efficacy of palonosetron, granisetron, and ramosetron for the prevention of PONV in patients undergoing laparoscopic gynecologic surgery. METHODS: In this prospective, randomized observational study, 105 healthy female patients who were undergoing laparocopic hystectomy under general anaesthesia were enrolled (clinical trial number: NCT01752374, www.clinicaltrials.gov ). Patients were divided into three groups: the palonostron (0.075 mg i.v.; n = 35), the granisetron group (3 mg i.v.; n = 35), and the ramosetron group (0.3 mg i.v.; n = 35). The treatments were given before the end of surgery. The incidence of PONV, severity of nausea/vomiting, and the use of rescue antiemetic requirements during the first 48 h after surgery were evaluated. RESULTS: The overall incidence of PONV was 33.3 % for this series. The number of complete responders at 48 h after the surgery was 21 (60.0 %) for palonosetron, 24 (68.6 %) for granisetron, and 26 (71.4 %) for ramosetron, representing no statistical difference (P = 0.086). CONCLUSIONS: There were no significant differences in the overall incidence of postoperative nausea and vomiting and complete responders for palonosetron, granisetron and ramosetron group. CLINICAL TRIAL NUMBER: NCT01752374 , www.clinicaltrials.gov .