Objective To observe the effect of Glutsmine on intestinal barrier function after traumatic brain injury in rats. Methods A total of 54 adult male Wistar rats were divided randomly into 3 groups, ie, normal group (Group N, 6 rats), TBI group (Group T, 24 rats) and Giutamine intervention group (Group G, 24 rats). Group T and Group G were subdivided into 4 groups according to detection time at days 1,3, 5 and 7 respectively. Meanwhile, 6 rats were enlisted in each group. The intestinal mucosa structure was detected by histopathological examination and electron microscopy. Apoptosis was detected by in situ immunohistochemical staining (TUNEL). Results Glutamine could relieve the pathological lesion of gut mucosa and decrease intestinal mucosa cell apoptosis after traumatic brain injury. Conclusion Glutamine can protect intestinal mucosa barrier function following traumatic brain injury.