There are about 800,000 patients suffering from traumatic brain injury (TBI) in China each year. The mortality rate of patients with severe TBI is about 27%. It is the leading cause of death and disability among young adults and has a great impact on society and families. TBI is divided into primary brain injury and secondary brain injury according to the pathophysiological mechanism. Primary brain injury is a direct result of mechanical injury factors, while secondary brain injury is based on the original brain injury. At the same time, the sum of extracranial injury and intracranial physical and biochemical changes has an important relationship with the prognosis of TBI. And a series of molecular, cell, tissue and organ level cascade reactions caused by neuroinflammatory reaction play an important role in the formation of secondary brain injury. Mesenchymal stem cell exosomes (MSCs-Exo), as a promising treatment for brain injury, can effectively reduce neuroinflammatory response and improve the prognosis of TBI. This article reviews the inhibition of neuroinflammation by mesenchymal stem cell exosomes after TBI. The mechanism of reaction and its treatment prospects are expected to provide a certain reference for follow-up research and treatment.