Ket or KET may refer to:

• Ket people, a people of Siberia
  • Ket language, the language of the Ket people
• Ket Sivan (born 1981), Cambodian swimmer who specialized in sprint freestyle events

• Ket (river), a river in Siberia
• Keť, a village in south-west Slovakia

• Ket (Greyhawk), a fictional nation in the Dungeons and Dragons World of Greyhawk campaign setting
• Ket and Wig, figures in the Gesta Danorum Danish history

• Cet mac Mágach, a character in Irish myth
• A name of the Celtic legendary figure Ceridwen

• KET, or Kentucky Educational Television, a non-commercial public television network
• Ketamine, a general dissociative anaesthetic
• Kettering railway station (National Rail station code KET), a station serving the town of Kettering in Northamptonshire, England
• Kengtung Airport, Burma/Myanmar (IATA airport code KET)
• Kennedy Town station (MTR station code KET), a station serving the suburb of Kennedy Town in Hong Kong
• Key English Test, an international examination sanctioning a basic level of the English language
• Key Enabling Technology, the technology that underlies the production of given goods or services
• Ket vallomas or Two Confessions, a 1957 Hungarian crime film
• The right part of bra–ket notation,
• Ket (software), an open source algebra editor

• Kit (disambiguation)