Duodenal duplication cyst is an uncommon congenital anomaly that is usually encountered during infancy or in early childhood. The clinical manifestation is that of duodenal obstruction or, less commonly, obstructive jaundice, acute pancreatitis, or gastrointestinal bleeding. Here, we report a case of duodenal duplication cyst on the juxtapapillary region in a 19-year-old woman with an unusual clinical manifestation of recurrent pancreatitis and peculiar endoscopic finding of the cyst. (Korean J Gastrointest Endosc 2004;28:218222)