Threshold may refer to:

In fiction:

• Threshold (Doctor Who), organization of Gallifreyan/Human origin in Doctor Who comic strips
• Threshold (fictional planet), the planet around which the ringworld Halo orbits in the video game Halo
• Threshold (comics), comic book character from Wildstorm
• Threshold (novel), a 1985 science fiction novel by David R. Palmer
• Threshold, a 1997 fantasy novel by Sara Douglass
• Threshold, a 2001 science fiction novel by Caitlín R. Kiernan
• The Threshold Project, a plot element from Sierra's PC game Phantasmagoria 2: A Puzzle of Flesh
• "Threshold" (Stargate SG-1), episode of the science fiction television series Stargate SG-1
• Threshold (TV series), science-fiction television series that began airing in 2005 on CBS and now airs on the Sci-Fi Channel
• "Threshold" (Voyager episode), episode in Star Trek: Voyager
• Threshold (2003 film), an adaptation of the 1958 movie It! The Terror from Beyond Space (which was also adapted into the 1979 film Alien)

In music:

• Threshold (band), progressive metal band from England
• Threshold (HammerFall album), album from the band HammerFall
• Threshold House, a record label
• Threshold Records, a record label
• Threshold, a song by the band Slayer from the album God Hates Us All

In science:

• Thresholding (image processing), segmenting an image into black or white for computer vision.
• Action potential threshold, point of the membrane potential curve at which action potential is initiated
• Lasing threshold, the minimum power level in optics at which a laser starts to operate
• Sensory threshold, one of the nine aspects of temperament in psychology

In politics:

• A electoral threshold is a portion of votes that must be attained before the candidate is truly considered; for example, a voting system with a threshold of 10% would mandate that all candidates need 10% or more to be counted on the ballot, with the left-over votes being distributed either equally or proportionately

In other fields:

• A synonym of doorstep
• Displaced threshold, runway threshold located at a point other than the physical beginning or end of the runway
• Election threshold, the minimal amount of votes necessary to win representation in an election
• Threshold RPG, text-based roleplaying MUD game