Objective To investigate the effect of diammonium glycyrrhizinate （DG） on neuronal activity， brain histopathology， and YAP1 protein in rats with traumatic brain injury.Methods A total of 44 rats were randomly divided into healthy group， trauma group （a rat model of traumatic brain injury）， edaravone group （the rats with traumatic brain injury were given edaravone intervention）， and DG group （the rats with traumatic brain injury were given DG intervention）， with 11 rats in each group. The Zea Longa method （5 points） was used to evaluate the nerve function of the rats in each group； enzyme-linked immunosorbent assay was used to measure the serum levels of interleukin-6 （IL-6）， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α）； HE staining was used to observe the morphological changes of neural cells in brain tissue； the TUNEL method was used to detect neuronal apoptosis in the hippocampal tissue of rats； Western blotting was used to measure the protein expression levels of YAP1， phosphorylated YAP1 （p-YAP1）， large tumor suppressor gene 1 （Lats1）， and extremely phosphorylated Lats1 （p-Lats1） in the hippocampus.Results Compared with the healthy group， the trauma group had significant increases in neurological score， IL-6， TNF-α， IL-1β， apoptosis of neural cells， YAP1， p-YAP1， Lats1， and p-Lats1 （P <0.05）. Compared with the trauma group， the edaravone group and the DG group had significant reductions in the above indicators （P <0.05）， while there were no significant differences between the edaravone group and the DG group （P >0.05）. Compared with the healthy group， the trauma group had disordered structure of the hippocampus， with a reduction in the number of neurons， hyperchromatic nuclei， and partial disappearance of cell membrane， and compared with the trauma group， the edaravone group and the DG group had ordered arrangement of neurons， with alleviation of swelling and clear nuclei.Conclusions Diammonium glycyrrhizinate has a positive effect on the treatment of cranial injury， which is similar to that of edaravone. Its mechanism may be related to improving nerve function， regulating the changes of inflammatory factors and the expression of related proteins.