He joined the Bay City Rollers in late 1973, The group's intense popularity, nicknamed "Rollermania", took off shortly afterwards. He was with the band until 1978, at which time he left to pursue a career as a solo artist. He released a series of solo albums which saw modest success, primarily in Germany and Japan.
He was ordered by Harlow magistrates on 23 August 2005 to appear at Chelmsford Crown Court on drugs charges, following his bail release. On 31 January 2006, McKeown admitted being a drug user but denied being a dealer. On 3 February 2006, he was acquitted of cocaine dealing. He suggested that he would sue the Metropolitan Police for earnings he lost from an overseas tour that was cancelled as a result of the proceedings.
Today McKeown resides in Hackney, England with his Japanese wife, Peko, and their son, Jubei. He still tours with his current band, "Les McKeown's Legendary Bay City Rollers" (he is the only former Roller in the band). The group appeared in the Countdown Spectacular two-concert series in Australia between late August and early September 2007. McKeown has completed two UK tours called Rollermania!, undertaken a UK tour of Once In A Lifetime with David Essex, Leo Sayer and The Osmonds and has, along with Alan Longmuir, appeared in the U.S. playing four dates as well as putting on a meet and greet fest for fans. McKeown was due to go back to the US, as well as Canada, at the end of September - beginning of October for more concert dates. Longmuir had agreed to join McKeown, but health problems meant he had to withdraw from the proposed tour.
McKeown developed a serious alcohol problem from about 2002, which resulted in him drinking a bottle of whisky per day. He underwent treatment in the Passages Clinic in Los Angeles which was documented in the Rehab reality TV programme that was broadcast on the Living Channel in the United Kingdom. In an interview with Scotland on Sunday in 2009, he talked about his sexual relationship with Tam Paton and his own bisexuality.
- Shang-a-lang: Life as an International Pop Idol Les McKeown, Lynne Elliott, Irvine Welsh, 2003 ISBN 1-84018-651-8.
- "UK | England | London | Rollers star faces drugs charge". BBC News. 2005-08-23. Retrieved 2012-01-01.
- "Former Bay City Rollers front man, Les McKeown, is ready finally to leave the past behind", Catherine Deveney, Scotland on Sunday, 15 February 2009
Stambler, Irwin, Encyclopedia of Pop, Rock & Soul. 1974. St. Martin's Press, Inc., New York, N.Y. ISBN 0-312-02573-4