The following fictional entities are set in the year 2003:

• In the video game Freedom Fighters, the game is set in an alternate timeline from 1945 on where world power shifted towards the Soviet Union, the Soviets invades and conquers the United States, causing a rebel resistance.
• In the TV series Stargate SG-1 the second alpha site is attacked by kull warriors.
• In The Simpsons timeline, the events of The Simpsons: Hit & Run take place between October 25 and October 31, with all seven levels taking place on one week.
• The events of Resident Evil: Extinction take place, before the last chapters of Resident Evil: The Umbrella Chronicles.
• The events of 28 Days Later commence in 2003, with the initial uprising of the Rage virus and decimation of Great Britain, and then the sequel 28 Weeks Later is also set later on in 2003, with the resurgence of the virus. The third film, 28 Months Later is to be set around 2005.
• In the last chapters of Resident Evil: The Umbrella Chronicles, Jill Valentine and Chris Redfield are sent to an Umbrella Fortress in February 2003.
• The Galactic Federation in the Metroid Backstory was formed in 2003.
• The main character in Osamu Tezuka's manga Tetsuwan Atom (1951) or Astro Boy was "born" on 7 April 2003.
• The 1981 arcade game Omega Race takes place in the year 2003.
• Mega Mom 2: Jack MLBP (1990) is set in February 7, 2003.