Daion is a Japanese guitar brand founded in 1967 in Osaka, originally as a wholesale distributor of musical instruments and the exclusive Japanese distributor of Yamaki guitars. The Daion brand of guitars emerged in 1978 when designer Hiro Teradaira created the first model in The Year Series, beginning with The '78. Production was handled by Yamaki, the company founded by the Teradaira family, and the Daion name was used for export markets — partly to avoid confusion with Yamaha in the United States.

The brand is best known for a relatively short but distinctive run of acoustic and electric instruments produced between 1978 and 1984. Notable lines include The Year Series and Heritage acoustic dreadnoughts, the Mugen Mark acoustic series, the Headhunter HH-555 semi-hollow electric, the Savage Series (Savage, Barbarian, Veteran, and Berserker models) and the Power Series, which featured unconventional design elements such as brass hardware and innovative body construction. The Performer Series rounded out the lineup with Stratocaster- and Les Paul-style configurations.

Daion guitars have developed a cult following among collectors and players for their build quality and distinctive designs from the late Japanese vintage era. Artists historically associated with the brand include members of Aerosmith, Fleetwood Mac, Asleep at the Wheel, Warren Haynes, Eddy Raven, and Split Enz.

Daion has 2 products cataloged on Equipboard, including Steel-string Acoustic Guitars and Electric Basses.