Harold Ashby (March 21, 1925 in Kansas City, Missouri – June 13, 2003 in New York City) was an American jazz tenor saxophonist. He worked with Duke Ellington's band, having replaced Jimmy Hamilton in 1968. In 1959, he recorded backing Willie Dixon on the latter's debut album, Willie's Blues.
Ashby worked as a freelance musician after leaving the Duke Ellington Orchestra in 1975, and took part in various reunions of Ellington alumni, as well as recording and gigging with his own bands.