To study the effect of rhubarb with different dosage in treating 62 cases of severe acute pancreatitis.Methods:Sixty-two cases of severe acute pancreatitis were selected as the research object from June 2013 to June 2014 and randomly divided into observation group and control group with 31 cases in each group.The observation group was treated with a large dose of rhubarb，and the control group was treated with a small dose of rhubarb.The effect of the treatment was compared between the two groups.Results:In the treatment group，bleeding occurred in 1 case，while 4 cases had edema，2 cases of bleeding and necrosis in 3 cases in the control group.The difference between the two group was statistically significant(P<0.05).After applying different doses in the two groups，the observation group’s remarkably curative effect rate was 67.74%(21 / 31)and the effective curative rate reached 96.77%(30/31)，which were significantly better than those of the control group(35.48% ［11/31］，70.97% ［22/31］.The difference between the two groups showed statistically significant(P<0.05).Symptoms score of patients in both the groups after treatment improved，but the observation group improved from(63.2±11.4)to(87.3±10.3)，significantly higher than that of the control group，showing statistically significant difference(P<0.05).Ranson and APACHEII score of patients in the two groups after treatment were improved but there was no significant difference(P>0.05).Conclusion:The large dose of Rhubarb for the treatment of SAP patients has good effect on the relief of abdominal distension and abdominal pain.