King could refer to:
- King (Kiva), the Bat Fangire/first Kamen Rider Dark Kiva.
- King Form, the name of the Final Forms of the BOARD Riders.
- King (OOO), the first Kamen Rider OOO, and the reason for the Greeed's existence.
- King (Undead), the human identity of the Category King of Spades Caucasus Undead.
- Daigo Kiryu, Kyoryu Red of the Sentai Team Zyuden Sentai Kyoryuger; "King" being Daigo's nickname and serves as a tongue-in-cheek reference to his Zyudenryu, a Tyrannosaurus rex, with "rex" meaning "king" in Latin.