Guyver may refer to:
- Guyver (surname), a surname (and list of people with that surname)
- Bio Booster Armor Guyver, a manga series that began in 1985 by Yoshiki Takaya and inspired several motion picture adaptations:
- Guyver: Out of Control, a 1986 animated feature film
- The Guyver: Bio-Booster Armor, a 1989 12-episode OVA series
- The Guyver, a 1991 live action film
- Guyver: Dark Hero, a 1994 live action film and sequel to the 1991 film
- Guyver: The Bioboosted, a 2005 26-episode anime series