This study developed and validated the children's voice questionnaire (CVQ), a new self-administered instrument for children, and evaluated its internal consistency and reliability. Observational, prospective, cross-sectional study. The initial preparation of the CVQ was conducted in four steps. First, individual interviews were conducted with dysphonic and non-dysphonic children and their parents, teachers, and speech pathologists. Second, the responses collected from the interviews were arranged into a comprehensive list of 175 items. Third, this list was reduced to a preliminary 21-item version of the questionnaire, which was tested as a pilot with 254 children. Fourth, a further reduction to 18 items was performed to construct the final version of the CVQ. The questionnaire was then administered to 342 children (73 dysphonic, 269 non-dysphonic) aged 6-18. Simultaneously, the parents of these children completed the pediatric voice handicap index (pVHI). Finally, after 2 weeks, 30 randomly selected children (nine dysphonic, 21 non-dysphonic) completed the CVQ again to evaluate test-retest reliability. High reliability was found for the CVQ (Cronbach's α=0.94). Test-retest revealed strong and statistically significant reliability (r=0.79, P<0.001). A highly significant group difference was found between the CVQ scores obtained for the dysphonic and non-dysphonic groups (t[78.25]=6.22, P<0.001). In addition, significant medium-to-strong positive correlations were found between the children's evaluations using the CVQ and their parents' evaluations using the pVHI (0.59<r<0.66, P<0.01). The newly developed CVQ is a valid and reliable instrument. Findings reveal general agreement between children and their parents, but also show that children's perspective on their dysphonia is not equivalent to the parent's perspective. This demonstrates that combining both perspectives provides a more holistic and complete overview of dysphonic children's voice-related quality of life. The self-administered CVQ reliably differentiates dysphonic from non-dysphonic children and may serve as a valuable tool for the initial or ongoing evaluation of children with voice disorders in clinical and research settings.