Objective:To Observe the related factors and the preventive measures of pancreatic infection in severe acute pancreatitis. Methods:138 cases were divided randomly into two groups group (infection group and non-infection group) according to whether secondary infection in two weeks after onset of pancreatitis, and analyzed predisposing factors. Results:There was significant difference between infection group and non-infection group in the hypoxemia, necrosis of pancreas, gastrointestinal tract dysfunction, operation, biliary pancreatitis(P < 0.05). Conclusion:Gastrointestinal tract dysfunction≥5 day, hypoxemia, necrosis of pancreas, biliary pancreatitis are principal predisposing factors of pancreatic infection in earlier period of SAP.