We outlined both the clinicopathological features of cystic lesions of the pancreas and the diagnostic imaging techniques, with a focus on ultrasonography, used to detect those lesions. Understanding the clinicopathological features of neoplastic cysts such as serous cystic neoplasms, mucinous cystic neoplasms, and intraductal papillary-mucinous neoplasms is linked to accurate diagnostic imaging of those cysts. Pancreatic endocrine tumors and solid-pseudopapillary tumors originally begin as solid tumors but frequently present with findings resembling a cystic neoplasm because of necrotic changes in the tumor. As a secondary cyst, retention cysts have important significance as an impetus for the detection of pancreatic cancer. Congenital cysts, which include cysts found in von Hippel-Lindau disease, cysts indicating polycystic disease, lymphoepithelial cysts, and epidermoid cysts, are seldom encountered and thus crucial. There are limited types of cystic lesions of the pancreas that are clinically important; if the pathological features of these types of lesions can be recognized and diagnosed with imaging, this will allow accurate clinical diagnosis. Moreover, if cystic lesions of the pancreas can be accurately diagnosed with imaging, unnecessary surgery can also be avoided.