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Deficits in executive function (EF) skills, or “higher order” cognitive processes, are particularly pervasive and problematic following pediatric traumatic brain injury (TBI), affecting academic, social, and functional outcomes. Extant studies indicate that the environment plays a role in the recovery process from pediatric TBI, including parental practices. In addition, a growing body of evidence suggests that an individual’s genetic makeup may also affect the recovery process. Studies have found an association between the dopamine receptor-4 (DRD4) 7-repeat allele and deficits in EF commonly seen after TBI; specifically, the DRD4 7-repeat allele has been associated with executive dysfunction in healthy children and is a well-known risk factor for the development of Attention Deficit Hyperactivity Disorder (ADHD). Research has also indicated that children with this allele are highly sensitive to the effects of experience or intervention, meaning that positive or negative effects of environmental factors (e.g., family functioning, therapeutic interventions) may be amplified in children with this allele. The present study examined the association of the 7-repeat allele and environment with neurocognitive and behavioral outcomes after pediatric TBI. For the present study, 113 participants (51 TBI and 62 orthopedic injury controls) were assessed 12 months post-injury and provided saliva samples for DNA extraction. Instruments assessing EF and environmental factors (i.e., parenting style, home environment) were collected. Regression analyses were utilized to examine the associations of genetics and TBI outcomes and possible interactions among hypothesized predictors of recovery. It was hypothesized that TBI and family environment would significantly moderate the association between the DRD4 7-repeat allele and EF, such that the association between the allele and EF would be amplified. It was further hypothesized that the presence of TBI, in addition to the quality of parenting style and home environment, would further amplify the associations of the DRD4 7-repeat allele with EF measures. We found evidence to partially support gene by environment interactions within our pediatric population; however, significant differences were found only in the 7-repeat negative group, which was counter to the original hypotheses. Our findings suggested that family environmental factors significantly influenced efficiency scores in two modified Stroop task subtests. Compared to the 7-repeat positive participants, in both models the 7-repeat negative participants did significantly better in the more positive family environment. We did not find evidence to support the hypothesis of gene by injury interactions, nor evidence to support the hypothesis of triple interactions. These findings were counter to our initial hypotheses and indicate that further work needs to be done to better understand the association of genetics with recovery after pediatric TBI. Larger studies are needed to determine the exact link between genotype and TBI recovery, and how this information can be used to inform prognosis and develop individualized treatment protocols.