Background: An emerging literature suggests that ethnic and cultural factors influence service utilisation among people with intellectual disability (ID), but this has not previously been reviewed. Aims: To investigate possible ethnic variation in uptake of mental health services in children, adolescents and adults with ID in high-income countries. Method: A systematic review using main databases of studies that consider ethnic influences on mental health utilisation of people with ID. Methodological quality of studies was assessed. Results: Nine studies that reached selection criteria were identified. Six studies that compared two or more ethnic groups found a variation in levels of mental health service utilisation. The most consistent finding was that South Asian children, adolescents and adults with ID in the UK had lower use of mental health services than White British comparison groups. Conclusion: Ethnic influences on mental health service utilisation were identified. Understanding their significance and potential negative consequences requires further investigation. (Contains 1 figure and 4 tables.)