Lesley Duncan (12 August 1943 – 12 March 2010) was an English singer-songwriter, best known for her work during the 1970s. She received a lot of airplay on British radio stations such as BBC Radio 1 and BBC Radio 2, but never achieved great commercial success.
Duncan was born in Stockton-on-Tees. Her songs included "Everything Changes" and "Sing Children Sing". Elton John duetted with her in a version of "Love Song" similar to his own, on his album Tumbleweed Connection. She appeared onstage with John in a 1974 concert at the Royal Festival Hall to perform the duet once again. The live recording of "Love Song" was included on John's Here and There album. The version on Tumbleweed Connection remains one of the few songs composed solely by someone other than John and Bernie Taupin or one of their regular collaborators, to appear on a formal Elton John studio album.
Duncan contributed backing vocals to Pink Floyd's The Dark Side of the Moon album as well as singing lead on the song "If I Could Change Your Mind" on the Alan Parsons Project album Eve. As well as writing and singing her own material, Duncan was a backing vocalist in the mid to late 1960s, most notably for Dusty Springfield and the The Walker Brothers. She co-wrote three songs with Scott Walker for the Walker Brothers.