James Hamilton, 2nd Duke of Abercorn (24 August 1838 - 3 January 1913) was a British nobleman and diplomat. He was variously styled Viscount Hamilton (until 1868), Marquess of Hamilton (1868–1885), and finally Duke of Abercorn (from 1885).

His full title was: The Most Noble James, 2nd Duke of Abercorn, Knight of the Most Noble Order of the Garter, Companion of the Most Honourable Order of the Bath.

Lord Hamilton was educated, like his father, at Harrow and Christ Church, Oxford. After graduating from Oxford with a B.A., he entered Parliament as Conservative MP for County Donegal, a constituency he represented from 1860 to 1880. After serving as Sheriff of County Tyrone, he re-entered university and emerged with an M.A. in 1865 (he was created a Companion of the Order of the Bath the same year). That year, he also embarked upon a diplomatic mission to Denmark. He served as a Lord of the Bedchamber to the Prince of Wales from 1866 to 1885; in the latter year, he inherited his father's position of Lord Lieutenant of County Donegal, and his father's peerage titles.

Abercorn held several positions after acceding to that title, including Grandmaster of the Ireland Freemasons (1886), Groom of the Stole (1886–1891), Chairman of the British South Africa Company, and announced Edward VII's accession to the throne in 1901 to several countries as a Special Envoy. He was also created a Knight of the Garter, and died of pneumonia in London at the age of seventy-three.