Matthew Justin Garrison was born June 2, 1970, in New York City, the son of bassist Jimmy Garrison, best known for his years in John Coltrane's classic quartet, and Roberta Escamilla Garrison, a modern dancer and choreographer. His father passed away from lung cancer in 1976, when Matthew was six, and much of his childhood afterward was spent in Rome, Italy. In 1988 he returned to the United States to live with his godfather, drummer Jack DeJohnette, who had played with John Coltrane's group as a guest and became an early mentor. The following year Garrison won a full scholarship to Berklee College of Music in Boston, where he met keyboardist Scott Kinsey, a schoolmate and later, longtime collaborator, and began playing professionally.

Garrison moved to New York City in 1994 and quickly built a sideman career on the strength of his hybrid technique, blending conventional electric bass with guitar-style chording, tapping, and outboard electronic processing. He spent the mid-to-late 1990s on the road and in the studio with a run of major bandleaders: Steve Coleman's Five Elements, Joe Zawinul's Zawinul Syndicate (contributing to Zawinul's Grammy-nominated 1996 album My People), guitarist John McLaughlin's new quintet on The Heart of Things (1997, with saxophonist Gary Thomas, keyboardist Jim Beard, and drummer Dennis Chambers), and John Scofield's band. He also became a member of the Gil Evans Orchestra and worked with Gary Burton, Ornette Coleman, and vocalists Chaka Khan and Joni Mitchell. In June 1992, during this same sideman period, Garrison had already taken part in a quintet session led by drummer Rashied Ali: alongside saxophonist Ravi Coltrane, son of John Coltrane, Garrison, son of Jimmy Garrison, sat in with the one drummer who had actually shared a bandstand with both their fathers. The tapes went unreleased for nine years, surfacing in 2001 as No One in Particular on Ali's own Survival Records.

At the start of 2000 Garrison came off the road to concentrate on his own music, releasing his self-titled debut, Matthew Garrison (2000, GarrisonJazz Productions), a largely self-performed, heavily overdubbed record built from bass, guitar, keyboards, and programming that Bass Player magazine credited with "raising the bar" for electric bass players. He founded his own label, GarrisonJazz Productions, to release it and his subsequent albums, among them Shapeshifter (2004), recorded across studios in New York and Rome between March 2003 and July 2004 with contributions from Kinsey, Jim Beard, harmonica player Gregoire Maret, percussionist Arto Tuncboyaciyan, drummer Jojo Mayer, and Garrison's half-sister, vocalist Joy Garrison. In 2007 he formed a power trio with Austrian guitarist Alex Machacek and drummer Jeff Sipe, recording Improvision for Abstract Logix, and in 2011 he joined Kinsey, drummer Gary Novak, and percussionist Tuncboyaciyan in the fusion quartet Human Element, whose self-titled debut echoed the Zawinul/Weather Report lineage all four members had passed through.

Garrison also kept a foot in more mainstream pop and R&B work, touring with Herbie Hancock (whose 2001 electronic-jazz album Future2Future and its subsequent live dates he played on) and with Whitney Houston's band during her 2010 "Nothing but Love" world tour. In 2016 he reunited with his two mentors' musical lineage on record: In Movement, a trio session with Jack DeJohnette and Ravi Coltrane recorded at Avatar Studios in New York and released on ECM, opened with a version of John Coltrane's "Alabama" and was widely reviewed as a meditation on the two families' intertwined jazz history. Also in 2011, alongside Fortuna Sung, a childhood friend from an international high school in Rome, Garrison co-founded ShapeShifter Lab, a performance space that opened in March 2012 in Brooklyn's Gowanus neighborhood; the club became a hub for improvised and experimental music before relocating to Brooklyn's Park Slope neighborhood around 2023 after pandemic-era financial pressure forced it out of its original space. Garrison has continued to record steadily into the 2020s, including Future Prime (2024) with guitarist Vernon Reid, and has built out GarrisonJazz Productions into an online music-education platform alongside his performing and production career.

Garrison is best known as one of the electric bass's most technologically minded stylists: rather than treating the instrument as a purely acoustic voice, he integrates guitar-style chordal playing, extended-range 5 and 6-string basses (he plays custom Fodera instruments), and a rig of loopers, synthesizers, and effects processors (Line 6, Native Instruments, and Ableton Live-based rigs across different periods of his career) to build dense, textured soundscapes live and in the studio. That approach places him in a lineage that runs from Jaco Pastorius through his own Zawinul Syndicate bandleader Joe Zawinul, and it made him a natural fit for John McLaughlin's and Steve Coleman's more harmonically and rhythmically adventurous fusion projects in the 1990s. As the son of Jimmy Garrison, he carries an unusually direct personal link to the Coltrane quartet's rhythm section, a connection made explicit on 1992's No One in Particular session with Rashied Ali and Ravi Coltrane and again on 2016's In Movement with Jack DeJohnette and Coltrane. Beyond performing, Garrison has shaped the New York scene institutionally: ShapeShifter Lab, the Brooklyn venue he co-founded and still runs, has given several generations of improvising musicians a stage of their own, in the tradition of loft-jazz spaces like Rashied Ali's own Ali's Alley a generation earlier.