This literature review aimed to synthesize evidence on the prevalence and determinants of health conditions and impairments among children and young people with intellectual disability in the United Kingdom. Several databases were systematically searched for studies conducted with children under the age of 18 living in the United Kingdom and published in 2010–11. Evidence from a 2002 and a 2010 literature review on health inequalities among individuals of all ages with intellectual disability was also reviewed. We conclude there is an increased prevalence of a number of health conditions and impairments among children with intellectual disability and evidence that these health inequalities are associated with several preventable environmental determinants.