Hypermobile Ehlers-Danlos syndrome (hEDS) includes physical symptoms of chronic pain, fatigue, gastrointestinal dysfunction, and joint subluxations/dislocations. This study aims to fill a research gap regarding the psychosocial well-being in pediatric hEDS by assessing relationships between functional disability, social support, and mental health. Increased functional disability is hypothesized to be associated with increased mental health challenges, specifically anxiety and depression, and general social support is hypothesized to moderate this relationship, such that higher perceived social support will mitigate the negative psychological impacts of functional disability. Gender's influence on mental health in pediatric hEDS is also explored. Thirty-four youth with pediatric hEDS recruited from a United States Midwest multidisciplinary genetics clinic completed self-report questionnaires. Results demonstrate associations between functional disability and mental health, and social support and mental health independently; however, moderation was not found. Functional disability and social support each have a unique influence on the mental health of children with pediatric hEDS and should each receive clinical attention. Exploratory analyses into the influence of gender provide a groundwork for future studies.