Hydrogen is a safe, convenient, non-toxic, bioactive gas with few side effects and selective antioxidant function. Hydrogen scavenging capacity has been shown to be protective against oxidative stress-induced damage. Hydrogen can pass through the blood-brain barrier, quickly cross cell membranes, and interact with toxic reactive oxygen species (ROS). It can be seen that hydrogen is effective in the prevention, treatment and alleviation of neonatal brain injury and cognitive dysfunction, especially in cerebral ischemia-reperfusion injury. Therefore, hydrogen has great potential in the clinical treatment of many neurological diseases. In addition, the protective effect of hydrogen on various tissue damages induced by radiation has also been reported. For example, the use of hydrogen-rich solutions after irradiation has been shown to mitigate damage to the immune system, hematopoietic system, skin, small intestine, and heart by reducing ROS. The selective neutralization of harmful oxygen radicals by hydrogen has attracted increasing attention in the field of radiation protection.