A percussion instrument is a musical instrument that is sounded by being struck or scraped by a beater (including attached or enclosed beaters or rattles); struck, scraped or rubbed by hand; or struck against another similar instrument. The percussion family is believed to include the oldest musical instruments, following the human voice.

The percussion section of an orchestra most commonly contains instruments such as timpani, snare drum, bass drum, cymbals, triangle, and tambourine. However, the section can also contain non-percussive instruments, such as whistles and sirens, or a blown conch shell. Percussive techniques can also be applied to the human body, as in body percussion.