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, and 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.

Grimes recorded or performed with pianist Lennie Tristano and saxophonists Lee Konitz, Gerry Mulligan and Sonny Rollins, pianists Thelonious Monk and McCoy Tyner, singer Anita O’Day, clarinetist Benny Goodmanand many others. 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.