Halo may refer to:

• Halo (religious iconography), a ring of light that surrounds an object in religious iconography
• Halo (optical phenomenon), a ring of light that surrounds an object
• Halo (medicine), used to immobilize cervical neck (spinal) fractures
• Halo (comics), a DC Comics superhero
• Halo (horse), an American thoroughbred racehorse
• Halo (visualization technique), a computer interface technique that uses arcs to point users to off-screen locations
• Halo, West Virginia
• Halo (bar), a gay bar in Washington, D.C.
• HALO or High Altitude Low Opening, a form of parachute jump
• Galactic halo, a ring of gas and stars surrounding a galaxy, and in particular the Milky Way Galaxy
• Halo (megastructure), the fictional ringworld/superweapons in the eponymous video game series

• Halo (1996 film) - Hindi film by Santosh Sivan
• Halo (2009 film)

• Halo, a video game series, consisting of:
  • Halo: Combat Evolved, a first-person shooter for the Xbox console, Windows, and Mac OS X
  • Halo 2, the sequel to the first game released on the Xbox and Windows
  • Halo 3, the last game in the series' main story arc released for the Xbox 360
  • Halo Wars, a real time strategy game based within the same fictional universe for the Xbox 360
  • Halo Chronicles, an episodic game based on the series' universe which is being developed by film director Peter Jackson

• BAE HALO ( Altitude Low Observability), a military aircraft under development
• SELEX Galileo HALO (Hostile Artillery Locator), acoustic weapon locating system.
• Mil Mi-26 or Halo, a heavy transport helicopter
• High Altitude Low Opening Parachute Jump

• Halo effect, a cognitive bias whereby the perception of a particular trait is influenced by the perception of the former traits
• Galactic halo, a region of space surrounding spiral galaxies
• Nuclear halo, a shape exhibited by some exotic atomic nuclei
• Halo-, a chemical prefix indicating halogen
• Halo orbit, a class of orbit around a Lagrange Point

• HALO is the numbering schema for albums released by the band Nine Inch Nails.
• Halo (Machine Head song), a heavy metal song by Machine Head
• Halo, a pop/rock song by Bethany Joy Galeotti (credited as Haley James Scott)
• Halo, a song by Porcupine Tree
• Halo, a song by Foo Fighters
• Halo (SOiL song), a heavy metal song by SOiL
• Halo (UK band) Four piece Bristol rock band
• Halo, a song from Bloc Party's forthcoming third album Intimacy.

• HALO Trust or Hazardous Areas Life-Support Organization, a charity for removing war debris
• Halo vehicle, an automobile marketing strategy
• Los Angeles Angels of Anaheim, sometimes referred to by fans or media as The Halos
• HALO: Hidden Alias List Operation, a fictional witness protection program in Charlie's Angels: Full Throttle
• Halo, a type of windmill breakdance move