John Howard Riley (b. 16 February 1943, Huddersfield) is an English jazz pianist and composer.
Riley began on piano at age six, and began playing jazz as early as age 13. He studied at the University of Wales (1961-66), Indiana University in America under Dave Baker (1966-67), and then at York University (1967-70). Alongside his studies he played jazz professionally, with Evan Parker (1966) and then with his own trio (1967-76), with Barry Guy on bass and Alan Jackson, Jon Hiseman, and Tony Oxley for periods on drums. Additionally he worked with John McLaughlin (1968), the London Jazz Composers Orchestra (1970-1980s), and with Oxley's ensemble (1972-81). He and Guy worked in a trio with Phil Wachsmann from 1976 well into the 1980s, and played solo piano throughout North America and Europe. From 1978 to 1981 he played in a quartet with Guy, Trevor Watts, and John Stevens; in the early 1980s he did duo work with Keith Tippett, with Jaki Byard, and with Elton Dean. From 1985 he worked in a trio setting with Jeff Clyne and Tony Levin.