To determine whether early coagulopathy affects the mortality associated with severe civilian pediatric trauma, trauma patients younger than 18 years admitted to a pediatric intensive care unit from 2001 to 2010 were evaluated. Patients with burns, primary asphyxiation, preexisting bleeding diathesis, lack of coagulation studies, or transferred from other hospitals more than 24 h after injury were excluded. Age, sex, race, mechanism of injury, initial systolic blood pressure, Glasgow Coma Scale score, Injury Severity Score, prothrombin time, partial thromboplastin time, platelet count, and international normalized ratio were recorded. An arterial or venous blood gas was performed, if clinically indicated. Coagulopathy was defined as an international normalized ratio greater than 1.2. The primary outcome was in-hospital mortality. Secondary outcomes were lengths of intensive care unit and hospital stay. Eight hundred three patients were included in the study. Overall mortality was 13.4%. The incidence of age-adjusted hypotension was 5.4%. Early coagulopathy was observed in 37.9% of patients. High Injury Severity Score and/or hypotension were associated with early coagulopathy and higher mortality. Early coagulopathy was associated with a modest increase in mortality in pediatric trauma patients without traumatic brain injury (TBI). In contrast, the combination of TBI and early coagulopathy was associated with a fourfold increase in mortality in this patient population. Early coagulopathy is an independent predictor of mortality in civilian pediatric patients with severe trauma. The increase in mortality was particularly significant in patients with TBI either isolated or combined with other injuries, suggesting that a rapid correction of this coagulopathy could substantially decrease the mortality after TBI in pediatric trauma patients. Copyright © 2013 by the Shock Society.