Oni (disambiguation)

Oni (鬼) are ogres or demons in Japanese folklore.

Oni may also refer to:
 * Oni (band), a Canadian progressive metal band
 * Oni Press, an independent comic book publisher
 * Ooni, the kings of Nigeria's Yoruba people
 * Oni–Adil, Indian composer
 * Miye Oni (born 1997), American basketball player
 * Oni Gozen, a Japanese female warrior from the 16th century
 * Oni, Maharashtra, a small village in Western India
 * Oni, Georgia, a town in Georgia
 * Oni (letter), the 16th letter of the three Georgian scripts
 * Oni: Thunder God's Tale, stop-motion series
 * Oni (video game), a 2001 third-person action video game made by Bungie
 * Onimusha, a series of action video games made by Capcom
 * Oni Aliens, foes in the Gantz manga
 * Oni, the title of an unfinished Akira Kurosawa script that was later adapted to a video game named Nioh
 * Oni, a race of aliens from the manga and anime Urusei Yatsura
 * The Oni, a primary antagonist in seasons 8-10 of the TV series Ninjago
 * Oni, an alternate form of Akuma that appears in the Super Street Fighter IV: Arcade Edition video game
 * Oni, an antagonist in the Mortal Kombat: Shaolin Monks video game
 * My Oni Girl, a 2024 anime film by Studio Colorido

ONI may refer to:
 * Office of Naval Intelligence, the United States Navy's intelligence agency
 * Office of National Intelligence, an Australian government intelligence agency
 * OpenNet Initiative, a project for tracking the use of Internet filtering and surveillance
 * ONI Systems Corporation, an optical networking company acquired by Ciena Corporation in 2002
 * ONI (Oxford Nanoimaging), a super-resolution microscope company
 * Oxygen Not Included, a simulation video game by Klei Entertainment
 * OASIS Neural Interface, a VR technology system used in Ready Player Two
 * Oceanic Niño Index, the numerical metric for El Niño used by the U. S government's NOAA