Chengqi Decoction from Treatise on Febrile Diseases by Zhang Zhongjing， is the representative formular of yang brightness fu-organ syndrome. Wu Jutong developed Chengqi Decoction by creating Xuanbai Chengqi Decoction， which embodied the idea of “simultaneous treatment of lung and intestine”， and widely used to treat phlegm heat obstructing lung， fu qi being obstructed， etc. We had carried out multi-centered randomized controlled study， in order to provide laboratory proof of Xuanbai Chengqi Decoction curing chronic obstructive pulmonary disease of phlegm heat obstructing， and brought to light biological mechanism of Xuanbai Chengqi Decoction which smooth stoma qi to disperse lung qi. RCT research had confirmed that Xuanbai Chengqi Decoction is effective for acute exacerbation of chronic obstructive pulmonary disease with phlegm heat syndrome; supplement novel TCM treatment for COPD. The mechanism of dispersing lung qi is associated with regaining oxidant / antioxidant balance， improve mucus hypersecretion， airway remodeling， mucosal immune， inflammatory reaction， neuropeptides etc. The finding of neuropeptide pathways in particular has provided laboratory proof of the Chinese formula.