Abstract： Objective： To observe the effect of modified Qingyi tang combined with jejunal nutrition therapy on intraabdominal pressure and prognosis of severe acute pancreatitis. Methods：A total of 94 cases of patients with severe acute pancreatitis were randomly divided into the control group and the observation group. The control group was treated with routine therapy，and the observation group was additionally treated with modified Qingyi tang combined with jejunal nutrition therapy based on the treatment of the control group. The changes in curative effect，symptoms，intra-abdominal pressures and relative indexes in the two groups were observed. Results：The length of hospital stay，duration of abdominal distension and the recovery time of serum amylase as well as intestinal function in the observation group were better than those in the control group，the difference being significant(P＜0.01). The intra-abdominal pressure，white blood cell counts，C-reactive protein and procalitonin in the observation group were all better than those in the control group， the difference being significant(P＜0.01). The curative effective rate was 97.87% in the observation group， higher than that of 80.85% in the control group， the difference being significant(P＜0.01). Conclusion： Modified Qingyi tang combined with jejunal nutrition therapy for patients with severe acute pancreatitis can effectively reduce their intra-abdominal pressures and the duration of abdominal distension， accelerate the recovery time of serum amylase and intestinal function， inhibit the inflammatory responses，and can improve the clinical effect and prognosis.