BackgroundPrepancreatic postduodenal portal vein is extremely rare, with only 13 cases reported in the literature.Case presentationA 55-year-old white woman presented to our emergency department with abdominal pain. She underwent a computed tomography of her abdomen, which showed a portal vein coursing anterolaterally to her pancreas and posteriorly to the first portion of her duodenum, constituting a prepancreatic postduodenal portal vein. Imaging revealed choledocholithiasis, requiring endoscopic sphincterotomy, but due to a history of a gastric bypass procedure, she was lost to follow-up after being referred to an advanced endoscopist. This represents the 14th reported case of prepancreatic postduodenal portal vein. ConclusionsAwareness of this rare anomaly is paramount, and will help surgeons and interventional radiologists to avoid complications related to inadvertent injury to the portal vein, which could be life-threatening.