Background: Scoliosis is one of the most common spinal deformities with subsequent decrease in pulmonary function. The effects of surgical correction on the pulmonary function of patients with adolescent idiopathic scoliosis are controversial. The purpose of the present study was to compare the postoperative pulmonary function changes in different surgical approaches chosen for its correction. Methods: Sixty-five patients with adolescent idiopathic scoliosis who had undergone corrective spinal surgery in Shafa Yahyaian Hospital since 1997 to 2007 and had documented preoperative pulmonary function test report, included in our study