The effects of illness and treatment of diabetes mellitus extend beyond medical outcomes. We therefore evaluated health-related quality of life (HRQOL) in children (aged 8–12 years) and adolescents (aged 13–16 years) with type 1 diabetes to compare their results with healthy peers and to identify HRQOL determinants. A total of 68 children and adolescents from a tertiary care clinic which specialises in the management of diabetes, completed the generic KINDL-R questionnaire. This instrument for children and adolescents has six dimensions and an additional module assessing condition-related HRQOL. Overall, the HRQOL was not different between patients with type 1 diabetes and healthy controls. In some areas, children and adolescents with diabetes reported a better HRQOL compared to healthy peers: adolescents reported better psychological well-being ( P <0.05) and="" children="" higher="" levels="" of="" well-being="" in="" the="" school="" domain=""> P <0.05). in="" general,="" children="" reported="" a="" better="" hrqol=""> P <0.05) than="" adolescents="" with="" type="" 1="" diabetes="" confirming="" age-related="" differences="" in="" hrqol="" in="" the="" general="" population.="" lower="" hba1c=""><8%) and="" intensified="" insulin="" therapy="" (="">3 injections/day) were associated with a better HRQOL in different domains ( P <0.05). the="" subscale="">chronic illness showed a better HRQOL ( P <0.001) in="" children="" and="" adolescents="" with="" diabetes="" compared="" to="" age-matched="" controls="" with="" other="" chronic="" conditions.=""> Conclusion:Children and adolescents from a paediatric department specialising in diabetes management report good health-related quality of life. Younger age, good metabolic control and intensified insulin therapy are associated with a better health-related quality of life. Dimensions of health-related quality of life appear to play different roles at different ages, emphasising the importance of the multidimensional health-related quality of life concept and the value of age-appropriate self-reports.