Peter Rowan (born July 4, 1942) is an American bluegrass musician and composer. He plays guitar, fiddle, dobro, banjo, bass, piano and mandolin. He has a wide vocal range and yodels. He was inducted into the International Bluegrass Music Hall of Fame in 2022.

Rowan was born in Wayland, Massachusetts to a musical family. From an early age, he had an interest in music and learned to play the guitar from his uncle. He was influenced by musicians such as the Lilly Brothers and Tex Logan at the Hillbilly Ranch, and formed his first rockabilly band the Cupids 1956.

Influenced by the blues musician Eric Von Schmidt, Rowan traded his electric guitar for an acoustic and began to play the blues. He was also influenced by the folk sound of Joan Baez. In college, he discovered bluegrass after hearing The Country Gentlemen and The Stanley Brothers. He soon discovered the music of Bill Monroe, and with some help from banjo player Bill Keith, he was invited to Nashville to audition for Monroe. Accompanied by Keith, Rowan went to Nashville and was hired in 1964 as songwriter, rhythm guitarist and lead vocalist of Monroe's Bluegrass Boys. His recording debut as a "bluegrass boy" took place on October 14, 1966 and he recorded a total of fourteen songs with Monroe, including the classic "Walls of Time" co-written with Monroe, before his tenure ended in the spring of 1967.

Rowan teamed up with David Grisman in 1967 forming the band Earth Opera which frequently opened for The Doors. In 1969, Rowan joined Seatrain. In 1973, Rowan, together with Richard Greene, Grisman, Bill Keith, and Clarence White, formed the bluegrass band Muleskinner. The band released one studio album.

The same year (1973), Rowan and Grisman formed Old & In the Way with Greene, Jerry Garcia, and John Kahn. He wrote the song "Panama Red" that year. Greene was later replaced by Vassar Clements. Old & In the Way disbanded in 1974; shortly thereafter, Rowan joined The Rowans, a reconstituted version of his brothers' band (The Rowan Brothers, who had recorded and toured since 1970) for three years. For a time, he was touring with Greene in Japan and playing clubs with fiddler Tex Logan. He also formed the Green Grass Gringos, as well as The Wild Stallions with Roger Mason and Jon Sholle.

Rowan joined The Mother Bay State Entertainers in 1963 and played mandolin on the three tracks the group contributed to the 1965 various artist record The String Band Project. He has recorded and performed with his brothers, Lorin and Chris, at various times, starting in 1972. He has composed songs performed by New Riders of the Purple Sage, including "Panama Red", "Midnight Moonlight" and "Lonesome L.A. Cowboy".

Rowan also features on the 1987 album In No Sense? Nonsense! by the UK band Art of Noise. He appears as "The Voice" (yodel) on "One Earth", the last song of the album.

Rowan collaborated with his daughter, Amanda Rowan, to write the song "On the Wings of Horses", which was recorded on Rowan's 1990 album Dustbowl Children and later recorded by Emmylou Harris on the 1992 Disney album Country Music for Kids. Rowan released Quartet (2007), the second collaboration with guitarist and bluegrass musician Tony Rice. Rowan contributed to the 2011 bluegrass tribute album to the British progressive rock band the Moody Blues, entitled Moody Bluegrass TWO...Much Love, singing lead vocal on Mike Pinder's song "Dawn Is a Feeling".