The county colours of an Irish county are the colours of the kit worn by that county's representative team in the inter-county competitions of the Gaelic Athletic Association (GAA), the most important of which are the All-Ireland Senior Football Championship and the All-Ireland Senior Hurling Championship. Fans attending matches often wear replica jerseys, and wave flags and banners in the county colours. In the build-up to a major match, flags and bunting are flown or hung from cars, buildings, telegraph poles, and other fixtures across the county, especially in those regions where GAA support is strong.

The Down County Board or Down GAA is one of the 32 county boards of the Gaelic Athletic Association (GAA) in Ireland, and is responsible for the administration of Gaelic games in County Down,.