Children and adolescents with intellectual disability are known to experience mental health disorders, but anxiety disorders in this population have received relatively little attention. Firstly, this paper provides a review of published studies reporting prevalence rates of anxiety disorders in children and adolescents with intellectual disability. Secondly, the paper reviews measures of anxiety that have been evaluated in children/adolescents with intellectual disability, and details the associated psychometric properties. Seven studies reporting prevalence rates of anxiety disorders in this population were identified, with reported rates varying from 3% to 22%. Two-one studies evaluating a measure of anxiety in a sample of children/adolescents with intellectual disability were identified. While these studies indicate that several measures show promise, further evaluation studies are needed; particularly those that evaluate the capacity of measures to screen for anxiety disorders, not only measure symptoms.