Chronic obstructive pulmonary disease (COPD) is characterized by airway obstruction with episodes of symptom exacerbation that contributes to the progression of the disease and progressive loss of lung function. The role of increase in oxidative stress, inflammation and marked reduction in the levels of endogenous antioxidants such as reduced glutathione (GSH) and lung GSH biosynthesizing enzymes is involved. GSH is one of the most important antioxidant defence systems in lung cells and is accountable for maintaining cellular redox status in endothelial cells, in maintaining intracellular GSH/Glutathione oxidized (GSSG) homeostasis. Level of Reactive Oxygen Species (ROS) in the lung is progressively increased in COPD patients. Reactive Oxygen Species released as a result of COPD may enhance the likelihood of a patient developing cardiovascular disease, diabetes and osteoporosis. As per the study of the Burden of Obstructive Lung Disease (BOLD) its global prevalence is of 10.1% and COPD is estimated to be the third leading cause of death. N-acetylcysteine possesses the sulfhydryl group responsible for antioxidant effects, directly scavenges ROS. Thus, it may prevent tissue damage to various organs by scavenging oxygen free radicals (e.g., superoxides). Researchers have shown higher NAC daily produces control on the activation of inflammatory factor like Nuclear Factor - NF-kb. Further, it was shown to produce positive effect on nuclear erythroid 2–related factor–2 transcription factor that has a crucial role as regulator of cellular redox status. Thus, NAC shows potential beneficial antioxidant and anti-inflammatory effect in COPD.