Red King

Red King may refer to:

• The red King playing card
• Red King (Ultra monster), a foe of the Japanese superhero Ultraman
• Red King (comics), a number of comics characters of the same name
• William II of England, commonly known as William "Rufus", or "The Red King"
• Rory "Red King" MacDonald, a Canadian MMA fighter
• The Red King (novel), a children's book by author Victor Kelleher
• The Red King (TV series), a 2024 British crime drama television series
• Red King (Through the Looking-Glass), a character in the Lewis Carroll novel Through the Looking-Glass
• An ancient king whose descendants are the main characters in Children of the Red King series of books by Jenny Nimmo
• Another name for the Crimson King from the works of Stephen King