Henry Grimes (November 3, 1935 – April 15, 2020) was an American jazz double bassist and violinist.

After more than a decade of activity and performance, notably as a leading bassist in free jazz, Grimes completely disappeared from the music scene by 1970. Grimes was often presumed to have died, but he was discovered in 2002 and returned to performing.

Henry Alonzo Grimes was born in Philadelphia, to parents who both had been musicians in their youth. He took up the violin at the age of 12, then began playing tuba, English horn, percussion, finally switching to the double bass at Mastbaum Technical High School. He furthered his musical studies at Juilliard and established a reputation as a versatile bassist by the mid-1950s. He recorded or performed with saxophonists Gerry Mulligan, Sonny Rollins, pianist Thelonious Monk, singer Anita O’Day, clarinetist Benny Goodman and many others. At a time when bassist Charles Mingus was experimenting with a second bass player in his band, Grimes was the person he selected for the job. One of his earliest appearances on film is captured in the Bert Stern documentary on the Newport Jazz Festival of 1958, Jazz on a Summer’s Day. Grimes was 22 years old, and as word spread among the musicians about his extraordinary playing, he ended up playing with six different groups in the festival that weekend: those of Benny Goodman, Lee Konitz, Thelonious Monk, Gerry Mulligan, Sonny Rollins, and Tony Scott. And though Henry’s name never even appeared in the festival’s printed program, New York Times critic Bosley Crowther took note of the remarkable young bassist and listed him as one of the festival’s primary players.