The Russian guitar (sometimes referred to as a "Gypsy guitar") is an acoustic seven-string guitar that was developed in Russia toward the end of the 18th century: it shares most of its organological features with the Spanish guitar, although some historians insist on English guitar descent. It is known in Russian as the semistrunnaya gitara (семиструнная гитара), or affectionately as the semistrunka (семиструнка), which translates to "seven-stringer". These guitars are most commonly tuned to an open G chord as follows: D2 G2 B2 D3 G3 B3 D4. In classical literature, the lowest string (D) occasionally is tuned down to the C.

The seven-string guitar adds one additional string to the more common six-string guitar, commonly used to extend the bass range or also to extend the treble range.