A case of pancreatic pseudocyst is presented which mimicked an intrahepatic mass both after selective hepatic arteriography and isotope (99m Tc-S-Co) evaluation of the liver. A previous upper gastrointestinal series and ultrasonograhpy had seemed to accurately establish the diagnosis of pancreatic pseudocyst. A pancreatic pseudocyst may pose as an intrahepatic mass lesion and this entity should be recognized as a pitfall in nuclear imaging of the liver.