John Lee Clayton Jr. (born August 20, 1952)[1] is an American jazz musician, classical double bassist, arranger, and composer.

In 1969, at the age of 16, he enrolled in Ray Brown’s jazz class at UCLA, beginning a close relationship that lasted more than three decades.

He has taught at the University of Southern California Thornton School of Music and has served as president of the International Society of Bassists.

He has composed and arranged for the Count Basie Orchestra, Diana Krall, Whitney Houston, Carmen McRae, Nancy Wilson, Joe Williams, Ernestine Anderson, Quincy Jones, Dee Dee Bridgewater, Natalie Cole, Till Bronner, and the Tonight Show Band.

In 2007, Clayton won a Grammy Award for Instrumental Arrangement Accompanying Vocalist(s) for the song "I'm Gonna Live Till I Die" by Queen Latifah.