Hartnagel is a German surname. Notable people with the surname include:
Anke Hartnagel (1942–2004), German politician Christian Härtnagel (born 1982), German businessman Fritz Hartnagel (1917–2001), German lawyer and soldier
See also Charlotte Schneidewind-Hartnagel (born 1953), German politician Elisabeth Hartnagel-Scholl (1920–2020), German centenarian Hartagel River