Mearns is a Scottish surname. Notable people with the surname include:
- Dave Mearns (born 1947), psychotherapist and author
- Barbara Mearns (born 1955), Scottish naturalist and biographer
- David Mearns (born 1958), United States-born marine scientist
- Edgar Alexander Mearns (1856–1916), American ornithologist and field naturalist
- Frederick Mearns (1879–1931), British footballer
- Ian Mearns, British Labour Party politician
- Levi R. Mearns (died 1896), American politician from Maryland
- Randy Mearns (born 1969), Canadian lacrosse player
- Sara Mearns (born 1986), American ballet dancer
- William Hughes Mearns (1875–1965), American educator and poet