OBJECTIVE: This study aims to evaluate retrospectively the electronic medical records of surgical patients who received intravenous patient-controlled analgesia, to identify potential relationships between the incidence and risk factors of postoperative nausea and vomiting (PONV). METHODS: Records of 6773 adult patients who received fentanyl-based intravenous patient-controlled analgesia after surgery at Chung-Ang University Hospital between January 1, 2010 and December 31, 2015 were reviewed. Multiple logistic regressions were used to identify risk factors for PONV. RESULTS: Of 6773 patients, 1216 (18.0%) were recorded to have PONV. In multiple logistic regression analysis, female gender, nonsmoking status, history of motion sickness or PONV, use of desflurane and nitrous oxide, and preintubation use of opioid analgesia were independent risk factors for PONV. CONCLUSIONS: Despite the use of antiemetic prophylaxis, 18.0% of patients with intravenous patient-controlled analgesia had PONV. Use of desflurane and nitrous oxide, in addition to risk factors included in the Apfel score (female gender, nonsmoking status, history of PONV or motion sickness, and use of postoperative opioids) were identified as independent risk factors. As the incidence of PONV was 2.8%, 6.0%, 11.7%, 15.2%, 21.1%, 50.0%, and 100% for patients who had 0, 1, 2, 3, 4, 5, and all these risk factors, respectively, risk-adapted, multimodal, or combination therapy should be applied for patients receiving general anesthesia.