Hepatic artery variations occur in about one-fourth of the population, are frequent questions on standardized surgery exams, and are often discussed on teaching rounds with an attending surgeon. Intraoperatively, it is important to be aware of possible vascular anomalies in order to prevent ligation or injury of an essential vessel. This case report describes an extremely rare vascular anomaly encountered during a pancreaticoduodenectomy (Whipple operation). Our patient was a middle-aged woman who was incidentally diagnosed with a cystic pancreatic lesion. During the operation, an aberrant middle colic artery was found to be originating from the gastroduodenal artery instead of its usual origin at the superior mesenteric artery. This anomalous middle colic artery has not been previously reported in a live patient. It underscores the importance of being aware of possible vascular variations that may be encountered intraoperatively in order to prevent morbidity and mortality.