Heyer is a surname. Notable people with the surname include:
- Carl Justus Heyer (1797–1856), German professor of forestry
- Conrad Heyer (1749–1856), one of the earliest-born men to have been photographed
- Friedrich Casimir Gustav Heyer (1826–1883), German professor of forestry
- Georgette Heyer (1902–1974), English novelist
- Hans Heyer, German racing driver
- John Heyer (1916–2001), Australian documentary filmmaker
- John Christian Frederick Heyer (1793–1873), American missionary
- John Henry Heyer (1831–1905), American politician
- Hans-Joachim Heyer (1920–1942), German Luftwaffe ace
- Laurie Heyer, American mathematician
- Sascha Heyer, Swiss beach volleyball player
- Shane Heyer, Canadian ice hockey linesman
- Stephon Heyer, American footballer
- Volker Heyer, German judoka
