Leo Lyons (born David William Lyons, 30 November 1943) is an English rock musician, who was also the bassist of the British late 1960s to 1970s rock group Ten Years After.
Lyons was born in Mansfield, Nottinghamshire, England. He first played with lead guitarist Alvin Lee in The Jaybirds. In 1967 there was a name change to Ten Years After. With this group, Lyons played at major rock festivals including Woodstock in 1969 and the Isle of Wight Festival on 29 August 1970. Ten Years After disbanded in 1976, although they later reformed several times in the 1980s and 1990s with all original members.
In 1975, he was hired as a studio manager by Chrysalis Records to re-equip and run Wessex Studios in London. He then produced UFO from 1974 to 1976. Later he started two commercial recording studios himself.
Lyons moved to Nashville, Tennessee in the mid-1990s, and was a staff songwriter for Hayes Street Music. He currently plays in a reformed Ten Years After, with new frontmanJoe Gooch. and also with Joe Gooch in new blues rock power trio "Hundred Seventy Split".