A resonator guitar or resophonic guitar is an acoustic guitar that produces sound by conducting string vibrations through the bridge to one or more spun metal cones (resonators), instead of to the guitar's sounding board (top). Resonator guitars were originally designed to be louder than regular acoustic guitars, which were overwhelmed by horns and percussion instruments in dance orchestras. They became prized for their distinctive tone, and found life with bluegrass music and the blues well after electric amplification solved the problem of inadequate volume.

Dobro is an American brand of resonator guitars owned by Gibson and manufactured by its subsidiary Epiphone. The term "dobro" is also used as a generic term for any wood-bodied, single-cone resonator guitar.