Oxidative Stress Response (OSR) is a defense mechanism used to maintain cellular homeostasis after an increase in levels of Reactive Oxygen Species (ROS). Due to ROS, cell components are vulnerable to damage including the membrane and DNA - which can impact essential functions and lead to cellular death. Without repair, damages caused by ROS have the potential to disrupt cell function in an irreparable manner. Bacterial cells respond to ROS using both endogenous and exogenous pathways depending on their method of metabolism and evolutionary ability. Bacteria have developed regulatory mechanisms to contain damage and are also known to use antioxidants as defense. In this review we will cover the damage induced by ROS to different cellular structures, and mechanisms of OSR used by bacterial cells to promote survival.