She was born Alexandra Elene MacLean Denny on 6 January 1947 in Wimbledon, in south London. She went to art school, worked as a nurse, and sang in folk clubs in the evening. She made a solo record before being discovered and taken into The Strawbs in 1967.

In 1968 she joined Fairport Convention and made three albums with them; then she made one with the short-lived group Fotheringay; and after that she released four solo albums. She also appeared briefly in the musical Tommy and guested with Led Zeppelin; on a 1972-3 tour of America she opened for Genesis and for Randy Newman, but at Fotheringay's 1970 concert at the Albert Hall, Elton John opened for them.

Sandy Denny was one of the best-known, most appreciated, and most influential figures in folk music of that time. She was married to Trevor Lucas and they had a daughter Georgia in 1977: for him she rejoined Fairport, of which he was a member, in 1974-5. (He was Australian and later was producer for the groups Redgum, The Bushwackers, and Goanna.)

She fell down stairs on 18 April 1978 and died of a brain haemorrhage on 21 April.

Her discs include:

Solo album
The Original Sandy Denny
with The Strawbs
All Our Own Work
with Fairport Convention
What We Did On Our Holidays
Unhalfbricking
Liege and Lief
with Fotheringay
Fotheringay
Solo albums
The North Star Grassman and the Ravens
Sandy
Like and Old Fashioned Waltz
with Fairport Convention
Live
Rising for the Moon
Solo albums
Rendezvous
Gold Dust -- Live at the Royalty (posthumous)