Pancreatitis is a chemical inflammation caused by the digestion of the pancreatic tissue itself, which is an aseptic inflammatory reaction. The presence of fever in patients with pancreatitis often indicates a complex condition or a combination of other conditions. Acute pancreatitis itself is a chemical reaction of pancreatic self-digestion, while the specific cause of fever is the activation of the inflammatory reaction while digesting the pancreas itself, which leads to the release of various inflammatory factors and a large amount of inflammatory exudation, and even the expansion of inflammation to the whole body, resulting in damage and impairment of multiple organ functions. Therefore, patients with pancreatitis develop fever because the inflammation is gradually amplified and exceeds the anti-inflammatory capacity of the body. If a patient has fever, he or she should be examined with clinical symptoms and signs, abdominal CT and liver function as soon as possible to rule out bile duct stones, cholangitis, lung infection and abdominal infection. If necessary, it is necessary to rule out the presence of severe acute pancreatitis, or even pancreatic necrosis, pancreatic abscess formation and other serious conditions. Treatment requires active anti-infection therapy, as well as maintaining the stability of the patient’s internal environment.