The main causes of fever 20 days after pancreatic body tail resection surgery may be intra-abdominal infection, respiratory system infection, etc. Usually, the disease can be eliminated by applying antibiotic drugs and general treatment. 1. Intra-abdominal infection: If the pancreatic-intestinal anastomosis is cracked, it is easy for the digestive tract fluid to leak into the abdominal cavity, which in turn causes abdominal infection and the symptom of fever. In this case, ampicillin, ceftriaxone sodium, levofloxacin and other antibiotics can be used as prescribed by the doctor to eliminate the inflammation. Secondly, patients should drink more water in moderation and actively supplement protein, energy and vitamins to provide a strong guarantee for treatment. Surgery again if necessary. 2. Respiratory system infection: after pancreatic body tail resection, the body’s immunity is weakened, so the respiratory system is easy to be invaded by germs and show fever. According to the results of drug sensitivity, you can choose the targeted drugs to treat, commonly used amoxicillin, azithromycin, cefuroxime, levofloxacin and so on. Pancreatic body tail resection 20 days after the fever symptoms, should be taken seriously, timely medical examination, to avoid serious consequences.