Background: X-linked hypophosphatemia (XLH) is a rare, progressive, phosphate-wasting disorder that compromises skeletal development in childhood. The international XLH registry (NCT03193476) is a non-interventional, observational, real-world data collection programme established in August 2017 in Europe and Israel, with enrolment open to patients of any age with XLH. Objectives: To describe real-world registry data on HRQL in paediatric patients with XLH at centres in France. Methods: Data to 30 January 2024 were analysed for paediatric patients (<18 years at registry entry) who registered between March 2019 and January 2023. HRQL was measured using age-appropriate versions of the PedsQL, completed by parents for children aged <8 years and self-completed by older children. The PedsQL comprises four domains – Physical, Emotional, School and Social Functioning – which are combined into Physical health and Psychosocial health summary scores and a total score. Scores range from 0 to 100, with higher scores indicating better HRQL. The first PedsQL completed after registry entry was analysed. Results: Of 170 French paediatric patients registered at data cutoff (59% female; mean age 9.6 years [SD 4.96; range 0.2–17.9]), PedsQL data were available for 96 (59% female; mean age at completion 8.1 years [SD 4.43; range 0.3–16.0]). PedsQL scores are presented in Table 1. Psychosocial Health Summary scores worse than Physical Health Summary scores for all age bands, with the Emotional Functioning scores indicating greatest detriment. Total scores were worse for 5–7-year-olds. Conclusion: This real-world HRQL data from 96 paediatric patients with XLH in France show the greatest detriments in those aged 5–7 year. Psychosocial scores were lower than physical health scores in paediatric patients of all ages.< Réduire