Kasuga was a Japanese stringed-instrument manufacturer founded in 1935 in Nagoya. The company built a wide range of fretted instruments — banjos, mandolins, classical and steel-string acoustic guitars, electric guitars, and basses — and grew into one of the larger names in postwar Japanese guitar making. By the late 1960s and through the 1970s, Kasuga had launched its own branded line and offered closely-styled copies of popular Gibson, Fender, and Martin designs, alongside sub-brands such as Heerby and Ganson.

The company is best remembered for the OEM work that came out of its Nagoya factory. After Tokai's mid-1970s export boom outstripped Tokai's own production capacity, a joint venture called Kasuga International was formed with Tokai USA, and Kasuga began producing instruments to Tokai's spec. Through the 1980s and into the 1990s the factory built guitars for ESP, Burny/Fernandes, the early Navigator line, Yamaha, Headway, and Saga, earning a reputation for solid build quality on Les Paul, Stratocaster, Telecaster, and dreadnought-style copies. Catalog model designations from the era — such as the F-series folk acoustics, D-series dreadnoughts, and G-series classicals — turn up regularly on the vintage market.

Kasuga also collaborated with Roland on early guitar-synth work in the 1970s. As Japanese OEM guitar production migrated to Taiwan in the 1990s, the company's contract business contracted, and Kasuga ceased operations in 1996. Surviving instruments — particularly 1970s acoustics and lawsuit-era electric copies — remain sought after by vintage Japanese guitar collectors.

Kasuga has 2 products cataloged on Equipboard, including Solid Body Electric Guitars.