The impact of pediatric traumatic brain injury (pTBI) on health-related quality of life (HRQoL) in children and adolescents remains understudied. Short scales have some advantages in terms of economy and administration over longer scales, especially in younger children. The aim of the present study is to psychometrically evaluate the six-item German version of the QOLIBRI-OS-KID/ADO scale for children and adolescents. In addition, reference values from a general German pediatric population are obtained to assist clinicians and researchers in the interpretation of HRQoL after pTBI. A total of 297 individuals after TBI and 1997 from a general population sample completed the questionnaire. Reliability, validity, and comparability of the assessed construct were examined. The questionnaire showed satisfactory reliability (α = 0.75 and ω = 0.81 and α = 0.85 and ω = 0.86 for the TBI and general population samples, respectively). The QOLIBRI-OS-KID/ADO was highly correlated with its long version (R2 = 67%) and showed an overlap with disease-specific HRQoL (R2 = 55%) in the TBI sample. The one-dimensional factorial structure could be replicated and tested for measurement invariance between samples, indicating a comparable HRQoL construct assessment. Therefore, reference values and cut-offs indicating clinically relevant impairment could be provided using percentiles stratified by factors significantly associated with the total score in the regression analyses (i.e., age group and gender). In combination with the cut-offs, the QOLIBRI-OS-KID/ADO provides a cost-effective screening tool, complemented by interpretation guidelines, which may help to draw clinical conclusions and indications for further diagnostics and therapy.