Background: Macromastia has been related with number of physical and mental issues in spite of the fact that it is basically a physiological condition. This study aimed to discuss the effect of reduction mammoplasty on pulmonary function tests and back pain in patients with macromastia. Patients and Methods: This is a clinical study including thirty female patients with macromastia suffered from back pain, all underwent reduction mammoplasty, we used three pedicles techniques for reduction mammoplasty; medial, superior medial and inferior pedicles. Regarding pulmonary function test (spirometry) and carbon monoxide diffusion test, pre-operative and 3 months postoperative was done. Back pain was assessed preoperative and 3 months post operative according to facial pain scale. Results: The mean preoperative Forced Expiratory Volume 1% in this study was 89.10±19.45% which significantly increased to 100.28±19.87% post-operatively (p=0.0010). Regarding Forced Vital Capacity in this study, it significantly increased from 86.22%±21.08% pre-operatively to 100.42% ±19.85% post-operatively (p