Patrick Donnelly (1878 – 13 August 1947) was an Irish nationalist politician and MP in the House of Commons of the United Kingdom of Great Britain and Ireland.
Donnelly was first elected as member of the Irish Parliamentary Party at the by-election of 2 February 1918, and re-elected in the 1918 UK general election, representing the South Armagh constituency. It was one of the six seats won by the IPP at the election, when he defeated the Sinn Féin candidate, after which he served as a member of the Nationalist Party of Northern Ireland until 1922.