McCullagh is a surname. Notable people with the surname include:
Colm McCullagh, Gaelic Football player for County Tyrone Crawford McCullagh (1868–1948), Unionist politician in Northern Ireland David McCullagh (born 1967), Irish journalist and author Declan McCullagh, American journalist and columnist for CBSNews.com Edward McCullagh (1912–1986), nationalist politician and farmer in Northern Ireland Francis McCullagh (1874–1956), war correspondent George McCullagh (1905–1952), Canadian newspaper owner 1936–1952 James McCullagh (1809–1847), Irish mathematician James Benjamin McCullagh (1854–1921), Anglican missionary in British Columbia John H. McCullagh (1842–1893), American law enforcement officer in New York Peter McCullagh (born 1952), Irish statistician from Northern Ireland Sheila K. McCullagh MBE (1920–2014), British author of children's books
See also McCullough