Branch duct intraductal papillary mucinous neoplasms (BD-IPMNs) are characterized by cystic dilation of secondary ducts clearly communicating with a normalsized main pancreatic duct and seem to have a less aggressive clinical course than those arising from the main duct. BD-IPMNs are related to pancreatitis but the causal relationship is unclear. We report a case of a 62-year-old woman initially thought to have pseudocysts complicated by idiopathic recurrent pancreatitis but was finally diagnosed with BD-IPMN leading to recurrent acute pancreatitis attacks. The patient had six episodes of acute pancreatitis over 5 years. An abdominal computed tomography scan revealed two cystic lesions of 2.0 and 1.5 cm in the pancreatic body, which appeared at the second episode of acute pancreatitis. Each pancreatitis episode improved with conservative treatment, but the cystic lesions increased in size to 2.5 and 3.5 cm during the late follow-up period. A distal pancreatectomy was performed under the diagnosis of recurrent pancreatitis caused by BD-IPMN. The pathological findings revealed BD-IPMN with moderate dysplasia. We herein present a case of BDIPMN mimicking pancreatic pseudocysts with a review of the literature.