BACKGROUND: This study investigated the relationship between initial lactate levels and both mortality and morbidity in critically ill pediatric trauma patients requiring intensive care. METHODS: This retrospective study at tertiary center's pediatric intensive care unit from January 2020 to June 2024 aimed to characterize trauma patients and assess admission lactate levels' prognostic value. RESULTS: A total of 190 critically ill pediatric trauma patients were included in the study. The mortality rate was 7.9%, with most deaths occurring within the first 48 hours of admission. Initial lactate levels ≥6.9 mmol/L demonstrated moderate predictive power (area under the curve [AUC], 0.878) for mortality. Pediatric Risk of Mortality III (PRISM III) score showed good predictive ability (AUC, 0.922), while Pediatric Trauma Scores exhibited variable predictive performance (AUC, 0.863). Higher initial lactate levels were significantly associated with severe brain injury, the need for intubation, and an increased incidence of thoracic or abdominal injuries. CONCLUSIONS: Initial lactate levels and PRISM III score are effective predictors of mortality in critically ill pediatric trauma patients. Lactate levels ≥5 mmol/L upon admission should prompt close monitoring and consideration of aggressive management strategies.