John Gilmore (September 28, 1931 – August 20, 1995) was an avant-garde jazz saxophonist known for his tenure with keyboardist/bandleader Sun Ra from the 1950s to the 1990s.

Gilmore grew up in Chicago and played clarinet from the age of 14. He took up the tenor saxophone while serving in the United States Air Forcefrom 1948 to 1952, then pursued a musical career, playing briefly with pianist Earl Hines before encountering Sun Ra in 1953.

For the next four decades, Gilmore recorded and performed almost exclusively with Sun Ra. This was puzzling to some, who noted Gilmore’s talent, and thought he could be a major star like John Coltrane or Sonny Rollins. Despite being five years older than Gilmore, Coltrane was impressed with his playing, and took informal lessons from Gilmore in the late 1950s. Coltrane’s epochal, proto–free jazz “Chasin’ the Trane” was inspired partly by Gilmore’s sound.

In 1957 he co-led with Clifford Jordan a Blue Note session which resulted in the album Blowing in from Chicago. The rhythm section featured Horace Silver, Curly Russell, and Art Blakey. In the mid-1960s, Gilmore toured with the Jazz Messengers and he participated in recording sessions with Paul Bley, Andrew Hill (Andrew!!! and Compulsion), Pete La Roca (Turkish Women at the Bath), McCoy Tyner (Today and Tomorrow) and a handful of others. In 1970 he co-led a recording with Jamaican trumpeter Dizzy Reece. His main focus throughout, however, remained with the Sun Ra Arkestra.