Abstract：Objective： To observe the effect of modified Yupingfeng powder and Bufei tang on inflammatory factors in serum and respiratory function in patients with chronic obstructive pulmonary disease(COPD) in stable stage. Methods：A total of 120 cases of COPD patients in stable stage were divided into the observation group and the control group according to the random number table method，60 cases in each group. The control group was given routine western medicine，and the observation group was additionally given modified Yupingfeng powder and Bufei tang based on the treatment of the control group. The clinical effect was compared between the two groups. The changes in levels of indexes of the lung function [forced vital capacity as a percentage of predicted value(FVC% pred)，forced expiratory volume in one second as a percentage of predicted value(FEV1%pred)，the ratio of FEV1 to FVC(FEV1/FVC)，and inspiratory capacity as a percentage of predicted value (IC% pred)]，the indexes of arterial blood gas [partial pressure of carbon dioxide(PaCO2)，partial pressure of blood oxygen (PaO2)，oxygen saturation(SaO2)，and potential of hydrogen(pH)]，and inflammatory indexes in serum [procalcitonin(PCT)， prealbumin(PA)，high- sensitivity C- reactive protein(hs-CRP)，and α1- antitrypsin(α1-AT)] were detected before and after treatment. Results：The total effective rate was 96.67% in the observation group，higher than that of 83.33% in the control group， the difference being significant(P＜0.05). After treatment， Chinese medicine syndrome scores in the two groups were decreased when compared with those before treatment， and the scores in the observation group were lower than those in the control group，differences being significant(P＜0.05). After treatment，IC%pred in the two groups was increased when compared with that before treatment，and IC%pred in the observation group was higher than that in the control group (P＜0.05). After treatment，PaCO2 in the two groups was decreased when compared with that before treatment，and PaO2， SaO2 and pH were increased；PaCO2 in the observation group was lower than that in the control group，and PaO2，SaO2 and pH were higher；differences were significant(P＜0.05). After treatment，the levels of PCT and hs-CRP in serum in the two groups were decreased when compared with those before treatment，and the levels of PA and α1-AT were increased；the levels of PCT and hs-CRP in serum in the observation group were lower than those in the control group，and the levels of PA and α1- AT were higher； differences were significant(P＜0.05). Conclusion： In the treatment of COPD patients in stable stage，modified Yupingfeng powder combined with Bufei tang can improve the lung function and indexes of blood gas，and relieve inflammatory response.