Longmuir is a surname. Notable people with the surname include:
Alan Longmuir (1948–2018), Scottish bass guitarist Bill Longmuir (born 1953), British golfer David Longmuir, head of the Scottish Football League Derek Longmuir (born 1951), Scottish drummer James Longmuir, Church of Scotland minister John Longmuir (poet) (1803–1883), Scottish minister, antiquary, poet and lexicographer John Longmuir (tenor), Scottish-born Australian tenor Justin Longmuir (born 1981), Australian rules footballer Troy Longmuir (born 1979), Australian rules footballer