Objective To investigate the effects of timing of enteral nutrition on immune function, intestinal function recovery and complications in patients undergoing pancreaticoduodenectomy. Methods 120 pancreatoduodenectomy patients from January 2016 to December 2017 in our hospital were randomly divided into group A (start nutrition support within 12h), group B (start nutrition support within 24 h) and group C (start nutrition support after 48h). The body weight, ALB, prealbumin, CD4+/CD8+, bowel sounds recovery time, anus exhaust time, defecation time, feeding time, extraction time of nasointestinal tube and postoperative complications in each group were analyzed. Results The body weight, ALB, prealbumin and CD4+/CD8+ in group B were significantly higher than that of group A and group C (P＜0.05). The bowel sounds recovery time, anus exhaust time, defecation time, feeding time and extraction time of nasointestinal tube in group were significantly lower than that of group A and group C (P＜0.05). The postoperative complications in group B was significantly lower than that of group A and group C, and the difference was statistical significance (P＜0.05). Conclusion The use of enteral nutrition in patients with 24h after pancreaticoduodenectomy can effectively improve the immune function and recovery time of intestinal function, and improve the quality of patients' prognosis.