Kilroy is a surname. Notable people with the surname include:
Alix Kilroy (1903–1999), one of the first two women to have entered the administrative grade of the British Civil Service by examinationBucko Kilroy (1921–2007), American football player and executive with the New England PatriotsHoward KilroyJames Kilroy (politician) (1890–1954), Irish Fianna Fáil politicianJames J. Kilroy (1902-1962), assumed to be the origin of the "Kilroy was here" expressionJoe Kilroy (born 1960), Australian rugby league playerMark Kilroy (born 1968), University of Texas at Austin student was killed in a human sacrifice ritual in Mexico.Mary Jo Kilroy (born 1949), American politician and U.S. Congresswoman from OhioMatt Kilroy (1866–1940), American baseball playerMatthew Kilroy, British Army murderer involved in the Boston MassacreMichael Kilroy, Irish politician and coach builderMike Kilroy (1869–1960), former American Major League Baseball pitcherShawn Kilroy (born 1964), retired Canadian ice hockey goaltenderThomas Kilroy (born 1934), Irish playwright and novelist