Abstract：Objective：To observe the clinical effect of Qingjin Huatan tang combined with antibiotic de-escalation therapy for severe pneumonia with syndrome of phlegm-heat obstructing lung. Methods：A total of 78 cases of patients with severe pneumonia with syndrome of phlegm- heat obstructing lung were selected，and divided into the treatment group and the control group according to the random number table method，39 cases in each group. The control group was given antibiotic de- escalation therapy，and the treatment group was additionally given Qingjin Huatan tang based on the treatment of the control group. Both groups were treated for 14 days. Clinical pulmonary infection score(CPIS)， nutrition indexes， blood oxygen indexes，and levels of inflammatory factors before and after treatment were compared between the two groups. The mechanical ventilation time was counted in the two groups. Results：After treatment，CPIS as well as levels of interleukin-6 (IL-6) and C-reactive protein(CRP) in the two groups were decreased when compared with those before treatment(P＜0.05)； CPIS and the two levels above in the treatment group were lower than those in the control group(P＜0.05). After treatment， levels of hemoglobin(Hb)， albumin(Alb)， and prealbumin(PAB) in serum as well as blood oxygen saturation， oxygenation index，and blood partial pressure of oxygen in the two groups were increased when compared with those before treatment (P＜0.05)；the three levels and the three indexes above in the treatment group were higher than those in the control group(P＜ 0.05). The mechanical ventilation time was(70.75±22.03) hours in the treatment group，and(106.61±23.94) hours in the control group，the difference being significant(P＜0.05). Conclusion：In the treatment of severe pneumonia with syndrome of phlegm- heat obstructing lung，the application of Qingjin Huatan tang combined with antibiotic de- escalation therapy can effectively regulate levels of Hb，AIb，and PAB in serum，improve blood oxygen saturation，oxygenation index，and blood partial pressure of oxygen，as well as relieve inflammatory response and shorten the mechanical ventilation time.