Postoperative ileus is common after surgery. One non-pharmacological intervention that has shown promising results in reducing the duration of postoperative ileus is chewing gum after surgery. However, this has not been investigated in upper gastrointestinal surgery such as pancreatic surgery. Hence the aim of this study was to investigate the effects of chewing gum treatment on patients undergoing pancreaticoduodenectomy due to pancreatic or periampullary cancer.