Mortlock is a surname. Notable people with the surname include:
John Mortlock (1755–1816), British banker and politicianStirling Mortlock (born 1977), Australian rugby playerBryce Mortlock (1921–2004), Australian architectDavid Favis-Mortlock (born 1953), English geomorphologist and musicianThe Mortlock family of Martindale Hall includedWilliam Ranson Mortlock (1821–1884), South Australian grazier and politician (father)William Tennant Mortlock (1858–1913), South Australian grazier and politician (son)