Amylase can be high in the presence of lesions in the pancreas and parotid organs. Amylase can be detected in blood and urine, and the changes in blood and urine can be used for the diagnosis of acute pancreatitis and the differential diagnosis of acute abdomen. Because the increase of amylase in blood is earlier and shorter in duration when lesions occur in parotid and pancreas, while the increase of amylase in urine is later and longer in duration, the clinical diagnosis is mainly based on the change in blood, and the change of amylase in urine is only for reference. In addition to pancreatic and parotid lesions that cause high amylase, there are also non-pancreatic diseases and non-parotid diseases, such as peptic ulcer, sedative, alcoholism, renal failure, etc.