Objective To study the relation between the TCM constitution and the lung function of asthmatic bronchitis children to lay a foundation to apply the TCM constitution theory in preventing and treating children asthmatic diseases.Methods Following the Zhu’s method

120 asthmatic bronchitis children were divided into normal constitution

phlegm-damp constitution

qi deficiency constitution

internal heat constitution

and both qi and yin deficiency constitution.Based on the Su’s method

the cases were classified into balance constitution

lung-spleen Ⅰ constitution

lung-spleen Ⅱ constitution

spleen-kidney Ⅰ constitution

and spleen-kidney Ⅱ constitution.Their lung function was tested and the TPTEF /Te and VPTEF/Ve of each constitution were analyzed.Results Of the 120 cases

37 ones （30.8%） were qi deficiency constitution;33 ones （27.5%） were phlegm-damp constitution;and 60 ones （50.0%） were lung-spleen Ⅱ constitution.Compared with those with normal constitution

the cases with the phlegm-damp constitution

qi deficiency constitution

internal heat constitution

and both qi and yin deficiency constitution had significantly lowered TPTEF/Te and VPTEF/Ve （P<0.01）.Compared with those with internal heat constitution and both qi and yin deficiency constitution

cases with phlegm-damp constitution and qi deficiency constitution had lowered TPTEF/Te and VPTEF/Ve （P<0.05）.Compared with those with balance constitution

the cases with the lung-spleen Ⅰ constitution

lung-spleen Ⅱ constitution

spleen-kidney Ⅰ constitution

and spleen-kidney Ⅱ constitution had significantly lowered TPTEF/Te and VPTEF/Ve （P<0.01）.Compared with those with lung-spleen Ⅰ constitution

spleen-kidney Ⅰ constitution

and spleen-kidney Ⅱ constitution

cases with lung-spleen Ⅱ constitution had lowered TPTEF/Te and VPTEF/Ve （P<0.05）.Conclusion The qi deficiency

phlegm-damp

and lung-spleen Ⅱ constitutions of the asthmatic bronchitis children tend to appear more frequently.All cases have lowered TPTEF/Te and VPTEF/Ve.The cases with phlegm-damp

qi deficiency

and lung-spleen Ⅱ constitutions have a severe small airway obstruction than those with other constitutions

and there exists injured lung function.