Abstract： Objective： To observe the clinical effect of Qingyi Tongfu Tiaofei yin combined with western medicine for severe acute pancreatitis(SAP) complicated with acute respiratory distress syndrome(ARDS) and its effect on inflammatory factors and indexes of blood gas analysis. Methods：A total of 80 cases of patients with SAP complicated with ARDS were divided into the control group and the observation group according to the random number table method，40 cases in each group. The control group was given western medicine， and the observation group was additionally given the oral administration of Qingyi Tongfu Tiaofei yin based on the treatment of the control group. Both groups were treated for ten days. The clinical effect was compared between the two groups. Levels of inflammatory factors and indexes of blood gas analysis before and after treatment were compared between the two groups. The recovery time of gastrointestinal function， mechanical ventilation time， and the hospitalization time in intensive care unit(ICU) were recorded. Results： The total effective rate was 90.0% in the observation group，higher than that of 67.5% in the control group(P＜0.05). After treatment， levels of interleukin-6(IL-6)，interleukin-8(IL-8)，and tumor necrosis factor-α(TNF-α) in the two groups were decreased when compared with those before treatment(P＜0.05)，and the three levels above in the observation group were lower than those in the control group(P＜0.05). After treatment，levels of partial pressure of carbon dioxide(PaCO2) and partial pressure of oxygen(PaO2) in arterial blood，as well as the ratio of partial pressure of oxygen in arterial blood to fractional concentration of inspiratory oxygen(PaO2/FiO2) in the two groups were increased when compared with those before treatment(P＜0.05)；the two levels above and the ratio in the observation group were higher than those in the control group(P＜0.05). After treatment， the remission time of abdominal pain，the time of anal exsufflation，the time of first defecation，the time of mechanical ventilation，and the hospitalization time in ICU in the observation group were shorter than those in the control group(P＜0.05). Conclusion： In the treatment of SAP complicated with ARDS， the therapy of Qingyi Tongfu Tiaofei yin combined with western medicine can relieve inflammatory response， improve indexes of blood gas analysis， promote recovery of gastrointestinal function，and shorten the hospitalization time.