Background Gastrointestinal complications after lung transplantation remain a common yet poorly defined problem. In this study we examine our experience with gastrointestinal complications after lung transplantation. Methods Between August 1990 and June 2005, we retrospectively analyzed 208 patients who had undergone lung transplantation (single, 65% [137 of 212]; double, 34% [72 of 212]; heart–lung, 0.5% [2 of 212]; living related, 0.5% [1 of 212]). Four patients were retransplanted. Gastrointestinal complications were defined as any post-transplant diagnosis related to the gastrointestinal tract. Results Ninety of 208 (43%) transplant patients developed 113 gastrointestinal complications during follow-up (median 3.5 years [62 days to 10.0 years]). Biliary etiology was the most common (12% [25 of 208]), requiring cholecystectomy in 13 patients. Diarrheal syndromes occurred in 21 patients (10%) with 2 patients requiring laparotomies. Small bowel obstruction and/or gastroparesis were present in 17 (5%) and 12 (6%) patients, respectively. Fourteen patients required surgical lysis of adhesions for small bowel obstruction and 7 patients underwent gastric drainage procedures. Three patients had peptic ulcer disease with 2 patients requiring laparotomy for perforated duodenal ulcer. Ten patients developed gastrointestinal bleeding with 1 requiring a colectomy. Three patients presented with diverticulitis and 2 required colectomy. Three patients required laparotomy due to intraperitoneal leakage of gastric secretions after gastromy tube placement. Eleven (16%) deaths were directly related to gastrointestinal complications. Of those patients who required a laparotomy for indications other than cholelithiasis, 9 (35%) died within 8 weeks. Conclusions Gastrointestinal complications are common after lung transplantation and are associated with considerable morbidity and mortality. Vigilance is required for early recognition and prompt treatment.