Background: Psychological morbidity in young people aged 10-24 years, with inflammatory bowel disease (IBD) is increased, but risk factors for and impacts of this are unclear., Aim: To undertake a systematic literature review of the risk factors for and impact of psychological morbidity in young people with IBD., Methods: Electronic searches for English-language articles were performed with keywords relating to psychological morbidity according to DSM-IV and subsequent criteria; young people; and IBD in the MEDLINE, PsychInfo, Web of Science and CINAHL databases for studies published from 1994 to September 2014., Results: One thousand four hundred and forty-four studies were identified, of which 30 met the inclusion criteria. The majority measured depression and anxiety symptoms, with a small proportion examining externalising behaviours. Identifiable risk factors for psychological morbidity included: increased disease severity (r(2) = 0.152, P < 0.001), lower socioeconomic status (r(2) = 0.046, P < 0.001), corticosteroids (P ≤ 0.001), parental stress (r = 0.35, P < 0.001) and older age at diagnosis (r = 0.28, P = 0.0006). Impacts of psychological morbidity in young people with IBD were wide-ranging and included abdominal pain (r = 0.33; P < 0.001), sleep dysfunction (P < 0.05), psychotropic drug use (HR 4.16, 95% CI 2.76-6.27), non-adherence to medication (12.6% reduction) and negative illness perceptions (r = -0.43)., Conclusions: Psychological morbidity affects young people with IBD in a range of ways, highlighting the need for psychological interventions to improve outcomes. Identified risk factors provide an opportunity to develop targeted therapies for a vulnerable group. Further research is required to examine groups under-represented in this review, such as those with severe IBD and those from ethnic minorities., (© 2016 John Wiley & Sons Ltd.)