Background: Blood glucose possesses all properties of an ideal serum marker of systemic injury. It is highly sensitive for cerebral cellular injury secondary to head trauma. Although the pathophysiology of hyperglycemia's neuropathic effect is not entirely clear, it has been reported that it aggravates ischemic acidosis, which in turn worsens brain edema. Objective: To determine the relationship of blood glucose elevation to outcome in pediatric traumatic brain injury to improve the management of polytrauma patients. Patients and methods: This was a prospective study conducted over 100 pediatric patients with traumatic brain injury admitted to Emergency Hospital Mansoura University over a year from December 2020 to December 2021. Results: There were statistically significant correlations between ICU length of stay (LOS) and Glasgow Coma Scale (GCS) score (either on admission or on discharge) and random blood glucose (RBG) and fasting blood glucose (FBG). However, there were statistically significant correlations between hospital LOS and GCS (on discharge only) and RBG and FBG. Random blood sugar (RBS) could be considered as positive significant predictor, while GCS on admission could be used as negative significant predictor of death among studied cases. RBG and FBG could be used as significant predictors of death among studied cases with high sensitivity, specificity, and accuracy of RBS and moderate sensitivity, specificity, and accuracy of FBS. Conclusion: In the context of pediatric populations, the current study suggested that hyperglycemia at an early stage could be used as a reliable predictor of the outcome of head trauma and its prognosis. A higher blood glucose level may be a threatening sign that predicts a poor prognosis and an increased risk of death.