War World may refer to:

• War World (series), collaborative science fiction books set in the CoDominium universe of Jerry Pournelle
• War World (video game), a 2005 mech combat video game
• Warworld, a fictional planet in the DC Universe
• "War World", a 2002 episode of Justice League
• Justice League: Warworld, a 2023 U.S. animated film based on D.C. Comics

• The War of the Worlds (disambiguation)
• World at War (disambiguation)
• World war (disambiguation)