Over 3,000 adults were surveyed.
The ESRI says prejudice against Travellers and Roma in Ireland, is at its highest in the Midlands and the South West.
A survey of over 3,000 adults was conducted last year as part of a joint research programme between the ESRI and the Department of Children, Equality, Disability, Integration and Youth.
Dr Frances McGinnity, Associate Research Professor with the ESRI says attitudes to Travellers were particularly negative in the West, South West and the Midlands regions.
Attitudes to Roma were more negative than to any group: