Intruder may refer to a person that enters a space without permision from the owner or lawful occupant. It may also refer to one of the following:

Film and television

• Intruder (film), a horror movie from 1989
• The Intruder (1962 film), a film by Roger Corman
• The Intruder (1986 film), a film by Jopi Burnama
• The Intruder (2004 film), a film directed by Claire Denis based on the essay by Jean-Luc Nancy
• The Intruder (Stargate Atlantis), an episode of the television series Stargate Atlantis

Literature

• The Intruder by John Rowe Townsend
• Intruder in the Dust by William Faulkner

Other

• A-6 Intruder, an American military aircraft
• Intrusion, a geological rock formation
• Intruder (band), a Serbian electronica/pop band
• The Intruders (GI Joe), a line of GI Joe action figures from the 1970s