Biliary stent insertion is a well-established treatment of bile duct obstruction. Stent migration is a late-onset complication and can be life-threatening. We present a case of proximal biliary stent migration to the portal vein. An upper endoscopy was performed, and the biliary stent was retracted. Bleeding was seen from the papilla of Vater. The hepatoduodenal ligament was explored, and the common bile duct was found fully adherent to the portal vein, with a fistula between the common bile duct and the portal vein. The patient underwent surgery with extrahepatic bile duct resection and hepaticoduodenostomy. The patient survived and was discharged without surgical postoperative complications on postoperative Day 8.