Emotion perception (EP) forms an integral part of social communication and is critical to attain developmentally appropriate goals. This skill, which emerges relatively early in development, is driven by increasing connectivity among regions of a distributed sociocognitive neural network and may be vulnerable to disruption from early-childhood traumatic brain injury (TBI). The present study aimed to evaluate the very-long-term effect of childhood TBI on EP, as well as examine the contribution of injury- and non-injury-related risk and resilience factors to variability in sociocognitive outcomes. Thirty-four young adult survivors of early-childhood TBI (mean [M], 20.62 years; M time since injury, 16.55 years) and 16 typically developing controls matched for age, gender, and socioeconomic status were assessed using tasks that required recognition and interpretation of facial and prosodic emotional cues. Survivors of severe childhood TBI were found to have significantly poorer emotion perception than controls and young adults with mild-to-moderate injuries. Further, poorer emotion perception was associated with reduced volume of the posterior corpus callosum, presence of frontal pathology, lower SES, and a less-intimate family environment. Our findings lend support to the vulnerability of the immature "social brain" network to early disruption and underscore the need for context-sensitive rehabilitation that optimizes early family environments to enhance recovery of EP skills after childhood TBI.