BACKGROUND: Health-related quality of life (HRQoL) has been a widely used measurement method in pediatric rehabilitation. Although self-reporting is the gold standard, parent reports are commonly used in adolescents with cerebral palsy. Explaining the agreement and differences between adolescent self-reports and caregiver/physiotherapist reports could provide a comprehensive perspective on adolescents with cerebral palsy. METHODS: Ninety-seven adolescent and parents and their physiotherapists completed the Pediatric Quality of Life Inventory (PedsQL). Intraclass Correlation Coefficients (ICCs) and The ‘paired sample-t’ test evaluated group agreement and differences. RESULTS: The agreement on HRQoL was found to be excellent between adolescent-caregivers (ICC: 0.876), adolescent-physiotherapists (ICC: 0.872) and caregiver-physiotherapists (ICC: 0.926). The agreement decreased from excellent to moderate in the Pain and Hurt (ICC:0.492-0.604) and Fatigue (ICC:0.484-0.604) subdomains. There was a significant difference between adolescent-parents reports and adolescent-physiotherapist reports (p<0.001), but no significant difference was found between caregiver and physiotherapist reports. CONCLUSION: Compared to physiotherapists and their families, adolescents with cerebral palsy perceive their health-related quality of life better. Although there is an excellent agreement between adolescents with CP, parents and physiotherapists, agreement decreases in subjective areas such as pain and fatigue.