Background: Laparoscopic Roux-en-Y gastric bypass excludes the biliary tree from traditional evaluation and treatment with endoscopic retrograde cholangiopancreatography (ERCP). Due to the initial rapid weight loss, gastric bypass patients have an increased risk of developing gallstones in the gallbladder as well as in the common bile duct. Various techniques to access the biliary tree have been described. The techniques are characterised by complexity and varying results. The aim of the present study was to assess both feasibility and outcome of laparoscopic-assisted transgastric ERCP in patients with gastric bypass. Methods: We retrospectively reviewed all laparoscopic transgastric ERCPs performed at Zealand University Hospital during the period January 2010 to January 2016. The main outcome was cannulation of the common bile duct. Secondary outcomes were length of hospital stay and surgical complications. Results: Thirty-one laparoscopic assisted transgastric ERCP procedures were performed in 29 patients. Indication was choledocholithiasis. All planned procedures were conducted with a 100% success in cannulation of the common bile duct. Median hospital stay was 2 days (range 1–22). Perforation of the wall of the gastric remnant occurred in two patients. The overall postoperative complication rate was 36%. Surgical complications were bleeding, haematoma and intra-abdominal abscesses. Conclusion: Laparoscopic assisted transgastric ERCP is feasible, but there are several complications related to the procedure. Thus, until better alternative treatments are developed, it is recommended that the procedure should be performed at centres with both high endoscopic and bariatric expertise.