In addition to the well known hemoglobin and myoglobin，neuroglobin is the third discovered oxygen-carrying globin，which is mainly expressed in brain. Because neuroglobin has a great affinity for oxygen，can reversibly bind oxygen and specifically supply oxygen to the brain，it plays an important part in uptake、 transportation and utilization of oxygen in nerve tissues. The up-regulated expression of neuroglobin in human brain implies that neuroglobin plays an important role in protecting neurons from cerebral ischemia/hypoxia injury. It will provide new sights and approaches for the clinical study of ischemic/hypoxic injury of brain.