Objective To explore the risk factors of postoperative nausea and vomiting(PONV) in elderly patients after gastrointestinal surgery. Methods Clinical data were collected from 1 021 elderly patients(age≥65 y) who underwent gastrointestinal surgery in Nanjing Drum Tower Hospital from January 2016 to December 2017 and retrospectively analyzed. According to the occurrence of PONV, the patients were divided into two groups. The two groups were compared for the differences in perioperative factors. Furthermore, the Logistic regression analysis was performed to investigate the independent risk factors correlated with PONV. Results The incidence of PONV was 7.3%. The most important risk factors for PONV were aging 75 y or older [odds ratio(OR)=1.74, P=0.027], female(OR=1.69, P=0.039) , intraoperative administration of sevoflurane(OR=2.32, P=0.013), duration of intraoperative hypotension>20 min(OR=1.64, P=0.048) , the use of postoperative opioid analgesics(OR=2.14, P=0.002) and postoperative infection (OR=2.03, P=0.009) . Further analyses suggested that the association remained to be statistically significant only in patients experiencing duration of intraoperative hypotension>20 min(OR=6.28, P=0.006). Conclusions The occurrence of PONV in elderly patients after gastrointestinal surgery is related to multiple perioperative factors. Maintenance of hemodynamic stability, avoiding the use of inhalational anesthetics, preventing postoperative infection and weakening postoperative pain reasonably may reduce the risk of PONV in elderly patients. Key words: Postoperative nausea and vomiting; Elderly patients; Gastrointestinal surgery