Objectives: The main aim of this research was to investigate factors which predict health-related quality of life (HRQOL) in adolescents with inflammatory bowel disease (IBD). A secondary aim was to investigate agreement between parent and adolescent reported HRQOL. A further aim was to investigate gender differences in reported HRQOL. Method: Fifty-seven adolescents attending a Gastroenterology outpatients’ clinic with IBD completed measures of anxiety (Spence children’s Anxiety Scale), depression (Beck Depression Inventory), self esteem (Rosenberg Self Esteem Scale), parental overprotection (Parental Bonding Instrument) and HRQOL (Pediatric Quality of Life Inventory –PedQL). Parents completed measures of anxiety (Beck Anxiety Inventory), depression (Beck Depression Inventory) and the parent version of the PedsQL. Questionnaires. Results: Adolescent and parental psychological functioning and maternal overprotection were found to predict HRQOL outcomes. Agreement on parent and self reported HRQOL was moderate to good across all domains. Females reported poorer HRQOL than males on domains of physical, social and psycho-social functioning. Conclusions: The influence of individual and parental psychological functioning on the quality of life of adolescents with IBD is highlighted. Psychological funcitoning, gender and parental agreement should be important considerations for health-care providers when assessing the HRQOL of adolescents with IBD.