Objective?To investigate the relationship between syndromes of traditional Chinese medicine (TCM) and lung function in patients with chronic obstructive pulmonary disease (COPD) at stable phase. MethodsBased on diagnostic criterion of TCM, five groups of symptoms of TCM about stable COPD were established including lung Qi deficiency, lung and spleen Qi deficiency, lung and kidney Qi deficiency, lung Spleen Kidney Qi deficiency, and deficiency of both Qi and Yin. A total of 300 cases which were up to the standard were differentiated into 5 groups by the symptoms. Some basic details and lung function of the patients were recorded, and then statistical analysis was performed to analyze the differences of lung function among groups. ResultsForced expiratory volume in the first second in descending order was lung Qi deficiency group, lung and spleen Qi deficiency group, lung and kidney Qi deficiency group, and lung spleen kidney Qi deficiency group (P<0.05). ConclusionThese findings suggest that with the progressing of COPD, the symptom type of TCM for COPD patients at stable phase may vary from lung Qi deficiency to lung and spleen Qi deficiency, or to lung and kidney Qi deficiency, and even lung, spleen and kidney Qi deficiency. Lung function tests help reveal substance and pathogenesis of TCM syndromes of patients with stable COPD, and provide evidence for the clinical syndrome.