Objective ; To study the pulmonary function changes before and after operation in infants with pectus excavatum( PE). Methods; Thirty - two patients under 3 years were selected as study group and thoracoplasty were performed in all cases. The same number of normal infants with identical basic conditions was chosen as control group. Lung function was measured before

3 and 12 months after operation respectively in study group and in control group. The effects of thoracoplasty on lung function in infants with PK was analyzed. Meanwhile the clinical results were assessed postoperatively. Results:TE/TI

% V - PK and V25/PK in study group were abnormal before operation and significantly improved 1 year after operation. Except that one had logical notch in thorax

all patients had satisfactory results. Conclusions; The effects of thoracoplasty on infants with PE under 3 years is satisfactory and the lung function could recover to normal about one year after operation.