Saito Guitars is a boutique Japanese electric guitar and bass manufacturer based in Kawaguchi, Saitama. The company was founded by luthier Masaaki Saito, who opened a repair shop in Tokyo in 1991 that developed a strong reputation for restoring vintage instruments before launching the SAITO Guitars brand in 2013. All instruments are built in Japan in small numbers, with CNC routing and CAD work handled in-house rather than outsourced.

The lineup centers on the S-Series, introduced in 2015 with the S-622 — an S-style guitar distinguished by a carved archtop body intended to reduce weight while improving resonance and sustain. Variants include the S-622CS, S-622CST, S-624, S-622TLC, S-622JMC, and S-724, alongside the S-Bass line (S-420b, S-521b and their CSJ variants). The BEYOND Series, including the flagship 622BEYOND, 33BEYOND, and CS BEYOND, represents the higher-end tier of the catalog.

Saito's instruments combine traditional Japanese lutherie with modern construction techniques and original body designs rather than direct replicas of vintage templates. The brand has drawn attention from international players and boutique dealers, and is often grouped with other high-end Japanese builders such as Tom Anderson–tier imports carried by specialty shops in Japan and Europe.

Saito Guitars has 16 products cataloged on Equipboard, including Solid Body Electric Guitars, Electric Basses, and Semi-Hollowbody Electric Guitars. Their gear is featured by 6 artists, with the strongest followings in Rock, Jazz, and Metal. Notable users include Sugi, Daijiro Nakagawa, and Y.K.C.