Cystic occupations in the tail of the pancreas are considered to be inflammatory diseases of the pancreas, benign tumors of the pancreas, and malignant tumors of the pancreas. 1. Pancreatic inflammatory disease: with acute and chronic pancreatitis, edema and exudation of the pancreas can occur. In the late stage of the disease, if the exudate cannot be absorbed in time, fluid accumulation will be formed. On imaging, cystic occupancy in the tail of the pancreas is presented. 2. Benign pancreatic tumors: benign pancreatic tumors, such as plasma cystadenoma, papillary tumor, mucinous cystadenoma, etc., can also show cystic space in the tail of the pancreas. 3. Malignant tumor of pancreas: malignant tumors of pancreas such as ductal cell carcinoma and interstitial cell carcinoma of pancreas may also present cystic space in the tail of pancreas. There may be other clinical reasons leading to cystic occupancy in the tail of pancreas. It is recommended to go to hepatobiliary surgery department as soon as possible in order to clarify the cause of the disease and standardize the treatment under the guidance of professional doctors, so as to avoid delaying the condition.