Abstract：Objective：To observe the clinical effect of Yiqi Huoxue Huatan Prescription combined with nutrition support on chronic obstructive pulmonary disease (COPD) complicated with acute respiratory failure. Methods：A total of 94 patients with COPD complicated with acute respiratory failure were divided into the control group and the observation group according to the random number table method ， with 47 cases in each group. The two groups were given routine treatment and nutrition support， and the observation group was additionally treated with Yiqi Huoxue Huatan Prescription. Before and after treatment， the total lymphocyte count (TLC)， serum albumin， partial pressure of oxygen (PaO2)， partial pressure of carbon dioxide (PaCO2)， oxygen saturation (SO2)， forced expiratory volume in one second (FEV1)，forced vital capacity (FVC)，FEV1/FVC and traditional Chinese medicine (TCM) syndrome scores of cough and expectoration，and dyspnea，as well as the average hospitalization time and cost，mortality rate and survival rate were compared between the two groups. Results： Before treatment， there was no significant difference being found in the comparisons of the levels of TLC and serum albumin between the two groups (P＞0.05)； after treatment， the above two levels in both groups were increased， and the above two levels in the observation group were higher than those in the control group (P＜0.05). Before treatment， there was no significant difference being found in the comparisons of PaO2， PaCO2， SO2， FEV1，FVC and FEV1/FVC between the two groups (P＞0.05). After treatment，the PaO2 levels in the two groups were decreased (P＜0.05)，and the PaO2 level in the observation group was lower than that in the control group (P＜0.05)；the levels of PaCO2，SO2，FEV1，FVC and FEV1/FVC were increased (P＜0.05)， and the above five levels in the observation group were higher than those in the control group (P＜0.05). The average hospitalization time in the observation group was shorter (P＜0.05)，and the average hospitalization costs was lower than those in the control group (P＜0.05). Before treatment， there was no significant difference being found in the comparison of TCM syndrome scores of expectoration and cough， and dyspnea between the two groups (P＞0.05)； after treatment， the above two scores in the two groups were decreased (P＜0.05)，and the above two scores in the observation group were lower than those in the control group (P＜0.05). The mortality rate was 4.26%，lower than that of 19.15% in the control group (P＜ 0.05). Conclusion：The application of Yiqi Huoxue Huatan Prescription combined with nutrition support for COPD complicated with acute respiratory failure can effectively increase the immunity of patients，promote the recovery of blood gas indexes and pulmonary ventilation function， with significant importance on improving the symptoms of expectoration and cough， and dyspnea， shortening the hospitalization time， reducing the medical costs and decreasing the mortality rate.