McIlhenny or McElhenny is an Irish surname commonly found in Donegal and Derry. They are a Sept of the Cenel Eogain race, son of Niall high king of Ireland. In Gaelic the name translates "servant of Saint Canice". Notable people with the surname include:
Alexander McIlhenny (1778–1835), American military officer, farmer, and diarist Bernice McIlhenny Wintersteen (1903–1986), American art collector, president of the Philadelphia Museum of Art (1964–1968) Don McIlhenny (1934–2023), American football player Edmund McIlhenny (1815–1890), American businessman and inventor of Tabasco sauce Edward Avery McIlhenny (1872–1949), American businessman and Arctic explorer Henry Plumer McIlhenny (1910–1986), American art collector John Avery McIlhenny (1867–1942), American businessman, Rough Rider, and politician Paul C. P. McIlhenny (1944–2013), American businessman and conservationist Walter Stauffer McIlhenny (1910–1985), American businessman and World War II Marine
McElhenny Hugh McElhenny (1928–2022), American football player Marcus McElhenney (born 1981), American attorney, Olympic rowing coxswain Rob McElhenny (born 1977), American actor and writer best known for It's Always Sunny in Philadelphia
McElheny Josiah McElheny (born 1966), American artist Victor McElheny (1935–2025), American science writer
See also McElhenney McElhinney