Even as a teenager Prior began to be interested in traditional British folk music. After she met Tim Hart, the two began from 1966 to act together and published in 1968 and '69 the album Folk Songs of Olde England, Vol 1 & 2 on a folk festival learned the two in the same year Ashley Hutchings know, with whom she later founded Steeleye Span.
In addition to her work with Steeleye Span was released in 1971 yet another album of Prior and Hart in the form of Summer Solstice. Later, she then married Rick Kemp, Steeleye Spans new bassist, who had replaced Hutchings, and with whom she has daughter Rose Kemp. In 1976, she teamed up with June Tabor to the folk duo The Silly Sisters together, the total recorded two albums. When Steeleye Span 1978 temporarily resolved, they published the same year her solo debut Woman in the Wings, for which she won as a producer Ian Anderson. As a guest singer, she left in 1976 on the Jethro Tull album Too Old to Rock 'n' Roll, Too Young to Die and Mike Oldfield Incantations 1978 in appearance. In 1979 she accompanied Mike Oldfield Exposed on the tour.
In 1980, she was then in Steeleye Spans Reunion back of the party and called in 1987 additionally the Carnival band to life. In the 1990s the Maddy Prior concentrated primarily on their solo work and returned in 2000 Steeleye Span for two years temporarily back.
2008 and 2009 Maddy Prior stops beside her appearances with other artists Courses in Stones Barn, ( Cumbria, England) which deal especially with the singing and the interpretation of English folk songs.