Roy Williams MBE (born 7 March 1937, Salford) is an English jazz trombonist.

Williams learned piano as a youth and did not play the trombone until he was 18. He served his National Service in the military in the late 1950s, then joined the trad jazz group of trumpeter Mike Peters and worked with Terry Lightfoot in the early 1960s.

In 1965 Williams became a member of Alex Welsh‘s band, which accompanied Ruby Braff, Wild Bill Davison, and Bud Freeman. Williams remained with Welsh until 1978, also collaborating with bandmate John Barnes in a side ensemble. He then worked with Humphrey Lyttelton (1978–1983), and in 1980 played with the Pizza Express All Stars and Benny Waters.