Benny Green was born April 4, 1963, in New York City and raised in Berkeley, California, the son of a tenor saxophonist whose record collection, heavy on Thelonious Monk and Charlie Parker, first pulled him toward jazz. He began classical piano lessons at seven and taught himself to improvise by imitating those records before he had any formal jazz instruction. His earliest professional work came accompanying singer Fay Carroll, then playing in school bands, a twelve-piece group led by bassist Chuck Israels, and, while still a teenager, Eddie Henderson's quintet. He passed through the Berkeley High School jazz program in the same years as saxophonists David Murray and Joshua Redman and multi-instrumentalist Peter Apfelbaum. After graduating he freelanced around the Bay Area for about a year before moving to New York in the spring of 1982.

In New York he studied privately with pianist Walter Bishop Jr., who encouraged him to work systematically through the history of jazz piano rather than settle into a single influence. A short stint with saxophonist Bobby Watson led, in April 1983, to the piano chair in Betty Carter's trio, where he stayed until 1987, absorbing her demanding, tempo-shifting accompanist's discipline; he plays piano on most of her Grammy-winning Look What I Got! (1988, Verve). In 1987 he joined Art Blakey's Jazz Messengers, recording Not Yet (1988, Soul Note) and I Get a Kick Out of Bu (1990, Soul Note) alongside saxophonist Javon Jackson, trumpeter Philip Harper, and trombonist Robin Eubanks, and remaining a Messenger through late 1989.

He had already begun recording as a leader in parallel, cutting two albums for the Dutch label Criss Cross: Prelude (1988), a quintet date with Peter Washington, Tony Reedus, Javon Jackson, and Terence Blanchard, and In This Direction (1989), a trio with Buster Williams and Lewis Nash. From late 1989 he worked in Freddie Hubbard's quintet, documented on Topsy: Standard Book (1992, Enja) and Live at Fat Tuesday's (1992, MusicMasters). Signing to Blue Note in 1990, he released a run of trio albums through the decade: Lineage (1990), Greens (1991, the recording debut of a twenty-year-old Christian McBride on bass), the live Testifyin'! (1992, recorded at the Village Vanguard), That's Right! (1993) and the Japan-only Blue Notes (1993, Somethin' Else), both with McBride and drummer Carl Allen, The Place to Be (1994, a trio-plus-horns date featuring Gary Smulyan on baritone saxophone), Kaleidoscope (1997, a rotating group with Antonio Hart, Stanley Turrentine, Russell Malone, Ron Carter, and Lewis Nash), and These Are Soulful Days (1999).

In 1993 Oscar Peterson, that year's Glenn Gould Prize laureate, named Green the first recipient of the City of Toronto's Glenn Gould Protege Prize in Music. That same year Green replaced Gene Harris in Ray Brown's trio, holding the piano chair until 1997 across a run of Telarc albums, including Bassface: Live at Kuumbwa (1993), Don't Get Sassy (1994), Seven Steps to Heaven (1995, with guitarist Ulf Wakenius and drummer Gregory Hutchinson), and Live at Scullers (1997), plus the three-bass summit SuperBass (1997), which paired Brown with John Clayton and McBride. Green and Peterson also recorded a two-piano duo album, Oscar & Benny (1998, Telarc), with Brown on bass and Hutchinson on drums.

Since 1997 Green has led his own trios and duos, recording Funky! (1998, Somethin' Else), his Telarc label debut Naturally (2000, again with McBride and Malone), the unaccompanied standards collection Green's Blues (2001), and two piano-guitar duo albums made in memory of Ray Brown with Russell Malone, Jazz at the Bistro (2003) and Bluebird (2004). He has recorded steadily for Sunnyside and Jazz Legacy Productions since 2011 with a trio of bassist Peter Washington and drummer Kenny Washington (no relation): Source (2011, produced by bassist John Lee), Magic Beans (2013), and, with bassist David Wong added to the chair, Live in Santa Cruz! (2015) and, with drummer Rodney Green (also no relation), Happiness! Live at Kuumbwa (2017). Then and Now (2018) added flutist Anne Drummond and vocalist Veronica Swift, and Benny's Crib (2020) continued that expanded lineup. He returned to unaccompanied piano for Solo (2023) and, recorded live at Dizzy's Club and the Piedmont Piano Company, Renovation! (2026), his first solo recording made in concert rather than in the studio. In 2010 he played piano throughout Anat Cohen's Clarinetwork: Live at the Village Vanguard (Anzic Records), a working quartet date at the Village Vanguard alongside Peter Washington and Lewis Nash. He continues to teach at Jazz Camp West in California and at Centrum's Jazz Port Townsend in Washington, and tours internationally with his trio.

Green names Art Tatum, Erroll Garner, Hank Jones, Ahmad Jamal, Phineas Newborn, and Bud Powell among his formative influences, with Oscar Peterson as his most direct model; critics have consistently placed his own playing in that same lineage, built on fast, hard-swinging block chords and a stride-inflected left hand in service of an unapologetically hard bop vocabulary rather than a search for new harmonic ground. He has summarized his own aim plainly: "for myself and a lot of musicians I admire, the main focus is to just swing and have fun, and share those feelings with the audience." That combination of technical command and old-school swing is exactly what drew a succession of veteran bandleaders, Betty Carter, Art Blakey, Freddie Hubbard, and Ray Brown, to build working bands around him during the 1980s and 1990s, and it has since made him a mentor-generation figure in his own right for younger hard-bop pianists.