The change of blood and urine amylase in acute pancreatitis is relatively regular. In the early stage of acute pancreatic attack, the blood amylase of patients will gradually increase in a few hours, and it will reach its peak in about 24 hours, and the value of blood amylase will gradually return to normal in 4-5 days. Urinary amylase is relatively slow to respond, and it will only gradually increase after 24 hours of onset and even reach its peak, and will only gradually return to normal in about 2 weeks depending on the condition. Clinical attention should be paid to the changes in blood and urine amylase in acute pancreatitis, which is not the only indicator to determine the severity of the patient’s condition. Some acute severe necrotizing pancreatitis may measure normal values when the blood and urine amylase is rechecked. Although the severity of pancreatitis can be judged based on blood and urine amylase changes in acute pancreatitis, it should also be combined with imaging manifestations such as pancreatic CT.