A 26-year-old woman was evaluated for a mass found by computed tomography (CT). Radiographically, the mass resembled a pancreatic cystadenoma. The patient had had left upper quadrant abdominal pain for several years and low grade fevers and indigestion for 5 months. At surgery, a unilocular cystic mass was found anteriorly and caudally to the tail of the pancreas in the lesser sac. The cystic structure was connected to the pancreas by a tubular structure, which was suture ligated and divided. A review of the literature revealed this cyst to be the fifth reported case of enterogenous cyst of the pancreas. The case is unique, differing from previous reports in that ciliated respiratory epithelium, transitional epithelium, gastric mucosa, a bilayered smooth muscle wall, and a serosal surface were present in the cyst wall.