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