Lighthorse or Light Horse most often refers to Light cavalry, but may also refer to:
- 2nd/14th Light Horse Regiment, Australian Army Regiment
- 3rd Squadron, 17th Cavalry Regiment (United States)
- Australian Light Horse, mounted infantry who fought in World War I
- Calcutta Light Horse, Indian Army reserve unit during the British Raj
- Henry Lee III, nicknamed "Light Horse Harry"
- Horse&Rider, magazine formerly called Light Horse
- Light Horse Regiment, South African Army unit
- Lighthorse (American Indian police)
- The Lighthorsemen (film), a 1987 feature film about an Australian Light Horse unit
- Rutherford's Light Horse expedition of July 1776
- South Alberta Light Horse