Background Postoperative nausea and vomiting (PONV) continues to be a common complication after surgery and anaesthesia with higher incidence. PONV increased recovery room time, expanded nursing care, seriously affected the patients postoperative recovery and satisfaction. Mechanisms of PONV are still not clear now. Objective We try to summarize current opinions upon PONV. Content There are some transmitters we’ve known about PONV: 5-HT3, dopamine, histamine, acetylcholine, substance P, etc. Risk scores to predict the occurrence of PONV are used increasingly to guide prophylactic antiemetic administration, but they still have some limitations. Trend Anesthetists should pay enough attention to PONV in order to achieve a PONV-free hospital.