<b><i>Background:</i></b> Nausea and vomiting are undesirable outcomes during the postoperative period. Vomiting may cause life-threatening pulmonary aspiration, as the airway reflex may not be fully restored postoperatively due to the residual effects of anesthetic and analgesic medications. <b><i>Objective:</i></b> The aim of this study is to determine the effective dosage of haloperidol against nausea and vomiting, as well as its adverse effects. <b><i>Materials and Methods:</i></b> A total of 250 female patients between the ages of 19 and 70, who were admitted for laparoscopic abdominal hysterectomy, were included in this study. The patients were randomized into five groups: placebo (<i>n</i> = 50) (Group I), haloperidol 2 mg (<i>n</i> = 50) (Group II), haloperidol 1 mg (<i>n</i> = 50) (Group III), haloperidol 0.5 mg (<i>n</i> = 50) (Group IV), and haloperidol 0.25 mg (<i>n</i> = 50) (Group V). The patients’ duration of anesthesia, duration of surgery, and nausea/vomiting scores were recorded, along with the antiemetic agents used. The Aldrete’s recovery scale was used as the postoperative recovery criteria. Data from the following variables were recorded for all patients at postoperative minute 30 and hours 1, 2, 3, 4, 6, 12, and 24: heart rate, systolic arterial pressure, diastolic arterial pressure, level of sedation, visual analog scale values, antiemetic need, patient satisfaction, side effects. <b><i>Results:</i></b> It was determined that 0.5, 1, and 2 mg doses of haloperidol were effective in preventing nausea and vomiting, and there was no difference in effectiveness between the 0.25 mg dose group and placebo. <b><i>Conclusion:</i></b> Haloperidol was found to be an effective agent against nausea and vomiting at a dose of 0.5 mg and can be administered at the doses of 0.5 mg to 2 mg.