OBJECTIVE: To investigate if Potentilla fulgens (P. fulgens) has any neuroprotective effects on traumatic brain injury in rats. STUDY DESIGN: Sprague-Dawley rats were subjected to traumatic brain injury with a weight-drop device using 300 g-1 m weight-height impact. Sixty-four rats were divided into 4 groups: group 1 (vehicle-treated control), group 2 (P. fulgens 400 mg/kg/day, intraperitoneally [i.p.]), group 3 (vehicle-treated trauma), and group 4 (trauma+P. fulgens 400 mg/kg/day, i.p.). Distilled water was used as vehicle. All rats were decapitated 5 days after the induction of trauma, and the protective effects of P. fulgens were evaluated by histological, immunohistochemical, and biochemical analyses. RESULTS: Administration of P. fulgens at a dose of 400 mg/kg/day provided significant improvement in all of the histological, biochemical, and immunohistochemical analyses after the induction of traumatic brain injury. CONCLUSION: Although further studies are necessary to evaluate the time- and dose-dependent neuroprotec-tive effects of P. fulgens, it may be a beneficial therapeutic agent for prevention of secondary neuronal damage following diffuse traumatic brain injury. © Science Printers and Publishers, Inc.