The rennin-angiotensin system(RAS)is an important hormonal regulation system. Studies have shown that activation of RAS is closely related to the pathophysiology of acute pancreatitis(AP). It is thought that the RAS is composed of the classical ACE-AngⅡ-AT1 axis and the new ACE2-Ang(1-7)-Mas axis. The ACE-AngⅡ-AT1 axis will exacerbate the aggravation of AP through pancreatic microcirculation disturbances, inflammation and oxidative stress. However, recent studies indicated that the new ACE2-Ang(1-7)-Mas axis may antagonize the function of the classical axis which will decrease the progress of AP. The imbalance of the two axes may determine the prognosis of AP. Regulation and maintenance the balance of the two axes may contribute to the treatment. This review will focus on the relationship between the two axes and the acute pancreatitis.