Infantile lobar emphysema is a pulmonary hyperinflation state that has the clinical features of an air block syndrome characterized by bronchial cartilaginous abnormalities or unknown origin. Left upper lobe was affected in most of the reported infantile lobar emphysema. Infantile lobar emphyema is divided into two categories. e.g., congenital and acquired. We have experienced a case of left lower lobe involved infantile lobar emphysema which had undergone left pneumonectomy. She had progressive signs of tension accompanied by mediastinal displacement, ventilatory and circulatory failure in infant period. Because of the combined left upper lobe hypoplasia, left pneumonectomy was performed. And there was no cartiliginous abnormality in pathologic finding. This is the first domestic case which was affected in the lower lobe and successful surgical repaired.