The Armagh County Board (Irish: Cumann Lúthchleas Gael Coiste Chontae Ard Mhacha) or Armagh 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 Armagh, Northern Ireland.

The county board is responsible for preparing the Armagh GAA teams in the various sporting codes; football, hurling, camogie and handball.

The county football team has won two All-Ireland Senior Football Championships in 2002 and 2024.

The county's most successful football club is Crossmaglen Rangers. Crossmaglen have won the Armagh Senior Football Championship on 45 occasions, the Ulster Senior Club Football Championship on 11 occasions, and All-Ireland Senior Club Football Championship on six occasions.

Armagh has a long tradition of football. Several clubs were already in existence before the formation of the County Board in 1889.

Armagh became only the second team to win the Ulster Senior Football Championship in 1890. In the early years of the GAA, a club that won its county championship went on to represent the county and would also wear the county colours. Armagh Harps represented Armagh in the Ulster final, beating Tyrone (Cookstown's Owen Roes), but losing to All-Ireland Champions Cork (Midleton) in the All-Ireland Semi-Final.

Despite early success at provincial level, national success at junior and minor level and All-Ireland final appearances in 1953 and 1977, it took until 2002, under manager Joe Kernan, for the Armagh county team to win a first All-Ireland Senior Football Championship title. The county won the All-Ireland Minor Football Championship, in 1949 and again in 2009, but lost the 1957 All-Ireland Minor Football Championship final to Meath.

Kieran McGeeney took over as manager of Armagh in 2015. In 2024, he led them to a first All-Ireland Senior final since 2003. Armagh won the final to secure the Sam Maguire Cup for the second time, beating Galway 1-11 to 0-13.