In the literature there are only three reported cases of spontaneous pneumothorax resulting from congenital cystic adenomatoid malformation in children under 1 year and for whom any resuscitative efforts were made. We present here a fourth case of a pre-term baby girl who was in perfect health, until she suffered a spontaneous pneumothorax as the initial manifestation of congenital cystic adenomatoid malformation of the lung at 10 weeks of age. Atypical segmentectomy with the use of stapling devices was successful. The characteristics of this particular manifestation are discussed.