ABSTRACT: Since November 2019, SARS Coronavirus 2 disease (COVID-19) pandemic has spread through more than 195 nations worldwide. Though the coronavirus infection affects all age and sex groups, the mortality is skewed towards the elderly population and the cause of death is mostly acute respiratory distress syndrome (ARDS). There are data suggesting the role of excessive immune activation and cytokine storm as the cause of lung injury in COVID-19. The excessive immune activation and cytokine storm usually occurs due to an imbalance in redox homeostasis of the individuals. Considering the antioxidant and free radical scavenging action of N acetyl cysteine (NAC), its use might be useful in COVID-19 patients by decreasing the cytokine storm consequently decreasing the disease severity. Therefore, we reviewed all the available resources pertaining to the role of reactive oxygen species (ROS) in cytokine storm and the mechanism of action of NAC in preventing ROS. We also reviewed the use of NAC in COVID-19.