Objective: To generate national estimates of the effect of injury severity on the incidence and associated resource utilization-related outcomes of deep vein thrombosis (DVT) among pediatric traumatic injury inpatient admissions in the United States. Methods: Data from the 2003 HCUP KID dataset were analyzed for 240,387 hospital stays (unweighted=146,512) for traumatic injury in patients =20 years old. Among these hospitalizations, cases of DVT were identified. Injury severity scores (ISS) were calculated using the ICDMAP90 software; four mutually exclusive categories corresponding to increasing severity were created. Weighted regression models estimated the effect of injury severity on the likelihood of DVT, controlling for patient- and hospital-specific characteristics. Additional models including interaction terms for DVT/injury severity category estimated the joint effect of these parameters on total costs and LOS. Results: Among traumatic injuries identified, 648 patients (0.27%) had an ICD-9-CM code consistent with DVT, similar to previous estimates in the literature. Among observations with complete data, moderate [ISS=9-15], severe [ISS=16-24] and critical [ISS=25+]) injuries increased the likelihood of DVT (Odds Ratio [p-value]=2.13 [<0.0001], 2.49 [0.0001], and 3.53 [<0.0001], respectively), as compared to minor injuries (ISS=0-8). Relative to minor injuries, severe and critical injuries among those with DVT (i.e., interactive effects) were associated with increased LOS. DVT and increasing severity each independently increased total costs, but interactive effects were not significant. Conclusion: In this study we quantify the effect of injury severity on the incidence and utilization-related outcomes of DVT among those with traumatic injury in a multi-payer US population. Increasing severity appears to increase the likelihood of developing a DVT. Further, new interventions that mitigate the development of DVT may reduce the economic burden of traumatic injury among pediatric hospitalizations. Clinicians and other decision makers should be aware of the relationship between injury severity and DVT development and resource utilization-associated outcomes.