Girolamo Frescobaldi (September 1583 - March 1, 1643) was one of the most important composers of keyboard music in the late Renaissance and early Baroque periods.

Frescobaldi was born in Rome. He studied under the organist at Ferrara, Luzzasco Luzzaschi, and is also considered to have been influenced by Carlo Gesualdo, who was in Ferrara at the time. Frescobaldi was first famous as a singer. He travelled in the Low Countries as a young man, before becoming became organist of St Peter's in Rome in 1608, a post he held until his death. Contemporary reports speak of massive crowds gathering to hear him play and improvise. From 1628 to 1634 he was organist at the court of the Medicis in Florence.

He wrote a large number of works for the organ and harpsichord, including toccatas, canzonas and ricercare (a generic name for any contrapuntal piece). Among his best known works is the Fiori musicali (1635), a collection of organ works designed to be played during the mass service. His vocal music, which includes a number of masseses, motets and madrigalss, and his instrumental music, including some trio sonatas, is less well known and generally considered to be of little importance.

Frescobaldi's music was a very important influence on later composers. Through his pupil Johann Froberger, his music travelled to Germany where it influenced Johann Sebastian Bach (Bach is known to have owned a copy of Frescobaldi's Fiori musicali).