Alvarez Yairi is a line of handcrafted acoustic guitars produced through a long-running partnership between Alvarez (distributed by St. Louis Music in the United States) and the K. Yairi factory in Kani, Gifu Prefecture, Japan. The collaboration began in the late 1960s when St. Louis Music's Gene Kornblum met master luthier Kazuo Yairi, and the first Alvarez Yairi instruments reached the U.S. market in 1970. Under Kazuo Yairi's direction, the factory built a reputation for concert classical and steel-string acoustics made from naturally seasoned woods, with hand-shaped necks, carved bracing, and individually voiced tops.

The range spans several tiers, including the flagship Masterworks series (all-solid, premium tonewoods), the Honduran all-mahogany models, the Stage series, and the Standard series, with body shapes covering dreadnought, grand auditorium, folk/OM, parlor, baritone, and classical. Features such as the FST-series scalloped bracing systems and LR Baggs electronics (including HiFi and Stage Pro Bronze pickups on acoustic-electric models) are common across the line. Vintage Alvarez Yairi dreadnoughts and classicals from the 1970s, built during Kazuo Yairi's early export years, remain sought after on the used market.

Kazuo Yairi passed away in 2014, but the Kani workshop continues under a team of veteran luthiers, some with more than fifty years of experience at the factory, maintaining the hand-built methods he established. Alvarez Yairi is distinct from Alvarez's lower-priced lines, which are produced in other overseas facilities, and sits alongside — but is not the same as — the K. Yairi brand sold directly by the factory in Japan.

Alvarez Yairi has 27 products cataloged on Equipboard, including Steel-string Acoustic Guitars, Acoustic-Electric Guitars, and Classical & Nylon-String Guitars. Their gear is featured by 28 artists, with the strongest followings in Rock, Folk, World, & Country, and Electronic. Notable users include Duncan Sheik, Thom Yorke, and Gustavo Cerati.