Surfactant Protein B (SP-B) is a crucial protein found in the lungs, specifically in the alveoli, where gas exchange occurs. It plays a vital role in the formation and function of pulmonary surfactant, a substance that reduces surface tension in the lungs, preventing the collapse of alveoli during exhalation. SP-B is essential for maintaining proper lung function and ensuring efficient breathing. Deficiencies or mutations in the SP-B gene can lead to serious respiratory issues, particularly in newborns, such as neonatal respiratory distress syndrome. Research on SP-B continues to enhance our understanding of lung diseases and potential treatments, highlighting its importance in respiratory health.