Educated at Robin Hill Secondary Modern and Breeze Hill School, Lees had no formal musical education, but took up playing the guitar when he was fourteen. Lees went on to study at Oldham School Of Art, where he met Stuart 'Woolly' Wolstenholme in 1964. They played together in The Sorcerers, playing Eddie Cochran-style rock and roll, and in The Blues Keepers, before forming Barclay James Harvest in 1967. He recorded a solo album, A Major Fancy, in 1972, but the release of this was tied up when the band changed record label. It was not released until 1977. He also recorded a solo single for Polydor in 1974, a cover of The Eagles track "Best of My Love". In 1998, musical differences saw the members of Barclay James Harvest agree to take a sabbatical. Lees again met up with Wolstenholme and formed Barclay James Harvest Through The Eyes of John Lees, and this band became John Lees' Barclay James Harvest.