A stringed instrument includes an elongated supporter 4, which is disposed in a sound box 1 so as to have both ends fixed to a side plate 1b of the sound box 1, and a vibration absorber 5 disposed between the supporter 4 and a sounding board 2. The supporter 4 has a projection 4b formed on a surface facing an inner surface of the sounding board 2. The projection is brought into contact with the vibration absorber 5 to press the vibration absorber 5 against the inner surface of the sounding board 2. The vibration absorber 5 is supported by the supporter 4 so as not to bring both ends 5' and 5' of the vibration absorber 5 into contact with an inner surface of the side plate 1b.