Background: Gastrodin (Gas) exhibits anti-inflammatory properties against diseases associated with the central nervous system (CNS). This study aimed to investigate the potential neuroprotective role of Gas in traumatic brain injury (TBI). Methods: A rat TBI model was established in male adult Sprague-Dawley (SD) rats by controlled cortical impingement (CCI), and lipopolysaccharide (LPS) was applied to induce the activation of BV2 microglia and HT22 hippocampal neurons. Neurological deficits, motor function and brain water content were evaluated in TBI rats. TUNEL and Nissl’s staining were applied to measure neuronal degeneration and apoptosis. Microglial activation, the mRNA and protein profiles of pro-inflammatory cytokines were tested by immunohistochemistry (IHC), quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Results: Gas significantly reduced neurological deficits, cerebral edema, and neuronal apoptosis and improved motor function in TBI mice. In addition, Gas inactivated microglia and blocked the production of pro-inflammatory cytokines on the damaged side of the TBI rat brain. In vitro, Gas attenuated BV2 microglia inflammation and reduced HT22 hippocampal neuronal apoptosis. On the other hand, Gas activated the PKA/CREB/BDNF pathway both in vivo and in vitro. Conclusions: Gas blocks microglial activation-mediated inflammation through the PKA/CREB/BDNF pathway, thereby improving neurobehavioral function after TBI, which provides a potential therapeutic benefit for treating TBI.