Abstract：Objective：To observe the effect of Tanreqing injection on arterial blood gas and serum inflammatory factors in senile patients with bronchial asthma. Methods： A total of 120 cases of senile patients with acute attack of asthma were selected and divided into the observation group and the control group according to the random number table method，with 60 cases in each group. The control group was treated with montelukast sodium based on routine treatment， and the observation group was additionally treated with Tanreqing injection based on the treatment of the control group. Indexes of inflammatory factors and arterial blood gas before and after treatment as well as clinical effects and adverse reactions were compared between the two groups. Results： The total effective rate was 85.00% in the observation group， significantly higher than that of 63.33% in the control group(P＜0.05). After treatment，levels of interleukin-6(IL-6)，interleukin-4(IL-4)， tumor necrosis factor-α(TNF-α)，partial pressure of carbon dioxide(PaCO2) and plasma lactic acid(Lac) in the two groups were decreased when compared with those before treatment(P＜0.05)， and levels of blood oxygen partial pressure(PaO2) were increased(P＜0.05). After treatment，levels of IL-6，IL-4，TNF-α，PaCO2 and Lac in the observation group were lower than those in the control group(P＜0.05)， and PaO2 level was higher(P＜0.05). The incidences of palpitation， nausea and vomiting，throat irritation were 23.33%，16.67% and 5.00% respectively in the observation group，significantly lower than those of 48.33% ， 36.67% and 18.33% in the control group(P＜0.05). Conclusion： Tanreqing injection combined with montelukast sodium in the treatment of senile patients with bronchial asthma can effectively enhance curative effect，reduce serum inflammatory factors and adverse reactions，and improve arterial blood gas.