Glen Matlock (born 27 August 1956, Paddington, West London) is an English bass guitarist most famous for being in the original line-up of the punk rock band the Sex Pistols. Drummer Paul Cook has said that Matlock came up with much of the music for the band's songs and most of the lyrics, while lead singer Johnny Rotten made some adjustments. Matlock is credited as a co-author on 10 of the 12 songs on Never Mind the Bollocks, Here's the Sex Pistols. He also continues to make his own records and tour with various bands, including the Sex Pistols.

Matlock left the Sex Pistols in late February 1977, the legend being that he was 'thrown out' because he "liked The Beatles." Although Matlock has said that one of his biggest influences is The Faces, the Beatles anecdote is fictional. A claim made by the Pistols guitarist Steve Jones, regarding how he thought it was bizarre that Matlock was "always washing his feet", has also been misquoted and misinterpreted as the cause of Matlock's firing from the group. In his autobiography, I Was a Teenage Sex Pistol, Matlock stated that he left the band of his own volition as he was "sick of all the bullshit". In the 2000 documentary The Filth and the Fury, the band members generally agree that there was tension between Matlock and Rotten, which Matlock suggests was exacerbated by Malcolm McLaren's attempts to pit the two men against each other. Matlock was replaced by Sid Vicious, and went on to form The Rich Kids, a New Wave power pop band, with himself as bass guitarist and singer, Midge Ure (guitarist, singer and keyboard player), Steve New (guitarist and singer) and Rusty Egan (drummer). After The Rich Kids he formed The Spectres with Tom Robinson Band guitarist Danny Kustow, and then Hot Club with guitarist James Stevenson and singer Steve Allen.