Abstract: Traumatic brain injury (TBI) continues to be a significant cause of morbidity and mortality worldwide. Despite significant progress in understanding the complex pathophysiology of TBI, the underlying mechanisms remain poorly understood. The primary brain damage is acute and irreversible. However, secondary brain injuries often develop gradually over months to years, creating an opportunity for critical therapeutic interventions. In the past decade, research on TBI biomarkers has seen significant progress. This progress has been driven by the diverse nature of TBI pathologies and the challenges they present for evaluation, management, and prognosis. TBI biomarker proteins resulting from axonal, neuronal, or glial cell injuries have been extensively studied and widely used. However, their detection in peripheral blood specimens may be limited due to difficulties in crossing the blood-brain barrier in sufficient quantities. Even with the advances made in TBI research, there remains a clinical need to develop and identify novel TBI biomarkers that can address these limitations and provide more accurate and accessible diagnostic tools.