This systematic review and meta-analysis analyzed the risk factors for postoperative nausea and vomiting (PONV) in patients after general anesthesia based on 31 studies with 355,117 patients. Patient factors include female gender (OR 2.39), motion sickness (OR 2.08), non-smoking (OR 1.70), migraine (OR 1.38), higher BMI (OR 1.06), younger age (OR 0.98), ASA II (OR 0.97), and ASA III (OR 0.84). Anesthetic risk factors include patient-controlled analgesia (OR 1.51), volatile anesthetics (OR 1.46), postoperative opioids (OR 1.32), longer duration of anesthesia (OR 1.31), intraoperative opioids (OR 1.22), N2O (OR 1.12), intravenous anesthesia (OR 1.12), and prophylactic fentanyl (OR 0.81). Of the surgical factors, breast surgery (OR 2.13), cholecystectomy (OR 2.07), abdominal surgery (OR 1.37), gynecological surgery (OR 1.34) and longer duration of surgery (OR 1.13) are statistically significant. The study identified significant risk factors related to the patient, anesthesia and procedure, which may serve as a basis for clinical prevention. He recommends a prospective study to confirm the findings.