Bio-Booster Armor Guyver (Viz Media) or Guyver (Chuang Yi Publishing) (強殖装甲ガイバー, Kyōshoku Sōkō Gaibā) is a long-running manga series written by Yoshiki Takaya. The Guyver itself is a symbiotic techno-organic (or biomechanical) device that enhances the capabilities of its host.
The manga was originally serialized in Tokuma Shoten's Shōnen Captain magazine beginning in 1985. When Shōnen Captain was discontinued in 1997, the manga was picked up by Kadokawa Shoten who subsequently re-released all of the previous graphic novels originally published by Tokuma. The manga is currently serialized in Kadokawa's monthly Shōnen Ace magazine. It has been licensed by Viz Media, Star Comics and Chuang Yi Publishing.