Objective To investigate the effect of dexmedetomidine on tissue inflammation and cell apoptosis in rats with traumatic brain injury (TBI).Methods A rat model of TBI was established. The rats were divided into experimental group and control group. The rats in the experimental group were given intraperitoneal injection of dexmedetomidine 6 μg/kg and those in the control group were given intraperitoneal injection of normal saline of the same volume. At 3 and 7 days after injury, ELISA was used to measure the levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), Western blot was used to measure the expression of caspase-3, and TUNEL was used to observe cell apoptosis.Results Dexmedetomidine treatment significantly reduced the concentrations of TNF-α and IL-1β (P<0.05) and the expression of caspase-3 (P<0.05) and inhibited the apoptosis of neural cells in traumatic brain tissue (P<0.05).Conclusions Dexmedetomidine exerts a marked neuroprotective effect by alleviating inflammatory response and inhibiting the apoptosis of neural cells in traumatic brain tissue.