The results of operative treatment of children with bilateral chronic unspecific inflammatory diseases of the lungs were studied in follow-up periods of up to 17 years. Among the 73 patients studied, 19 had a history of bilateral and the remaining a history of unilateral resections. According to the findings of respiratory function examination, a combined type of ventilation disorders with mild hypoxemia and hypercapnia was characteristic of this group of patients before the operation. In the postoperative period the restrictive syndrome intensifies because the volume loss is not compensated for. There is a discrepancy between the clinical and functional data in evaluation of the results of the operation. However, in cases of good clinical results after extensive resections of the lungs a positive dynamics of the ventilation capacity of the lungs with increased oxygen tension in the arterial blood is recorded.