After completing his secondary education, Scott-Heron decided to attend Lincoln University in Pennsylvania because Langston Hughes (his most important literary influence) was an alumnus. It was here that Scott-Heron met Brian Jackson with whom he formed the band Black & Blues. After about two years at Lincoln, Scott-Heron took a year off to write the novels The Vulture and The Nigger Factory. Scott-Heron was very heavily influenced by the Black Arts Movement. The Last Poets, a group associated with the Black Arts Movement performed at Lincoln in 1969 and Abiodun Oyewole of that Harlem group said Scott-Heron asked him after the performance, “Listen, can I start a group like you guys?” Scott-Heron returned to New York City, settling in Chelsea, Manhattan. The Vulture was published by the World Publishing Company in 1970 to positive reviews.

Scott-Heron began his recording career with the LP Small Talk at 125th and Lenox in 1970. Bob Thiele of Flying Dutchman Records produced the album, and Scott-Heron was accompanied by Eddie Knowles and Charlie Saunders on conga and David Barnes on percussion and vocals. The album’s 14 tracks dealt with themes such as the superficiality of television and mass consumerism, the hypocrisy of some would-be black revolutionaries, and white middle-class ignorance of the difficulties faced by inner-city residents. In the liner notes, Scott-Heron acknowledged as influences Richie Havens, John Coltrane, Otis Redding, Jose Feliciano, Billie Holiday, Langston Hughes, Malcolm X, Huey Newton, Nina Simone, and long-time collaborator Brian Jackson.

Scott-Heron’s 1971 album Pieces of a Man used more conventional song structures than the loose, spoken-word feel of Small Talk. He was joined by Jackson, Johnny Pate as conductor, Ron Carter on bass and bass guitar, drummer Bernard “Pretty” Purdie, Burt Jones playing electric guitar, and Hubert Laws on flute and saxophone, with Thiele producing again. Scott-Heron’s third album, Free Will, was released in 1972. Jackson, Purdie, Laws, Knowles, and Saunders all returned to play on Free Will and were joined by Jerry Jemmott playing bass, David Spinozza on guitar, and Horace Ott (arranger and conductor). Carter later said about Scott-Heron’s voice: “He wasn’t a great singer, but, with that voice, if he had whispered it would have been dynamic. It was a voice like you would have for Shakespeare.”

Although Scott-Heron never completed his undergraduate degree, he was admitted to the Writing Seminars at Johns Hopkins University, where he received an M.A. in creative writing in 1972. His master’s thesis was titled Circle of Stone. Beginning in 1972, Scott-Heron taught literature and creative writing for several years as a full-time lecturer at Federal City College in Washington, D.C. while maintaining his music career.

1974 saw another LP collaboration with Brian Jackson, the critically acclaimed opus Winter in America, with Bob Adams on drums and Danny Bowens on bass. The album contained Scott-Heron’s most cohesive material and featured more of Jackson’s creative input than his previous albums had. Winter in America has been regarded by many critics as the two musicians’ most artistic effort. The following year, Scott-Heron and Jackson released Midnight Band: The First Minute of a New Day. 1975 saw the release of the single “Johannesburg”, a rallying cry to the issue of apartheid in South Africa. The song would be re-issued, in 12″-single form, together with “Waiting for the Axe to Fall” and “B-movie” in 1983.

A live album, It’s Your World, followed in 1976 and a recording of spoken poetry, The Mind of Gil Scott-Heron, was released in 1978. Another success followed with the hit single “Angel Dust”, which he recorded as a single with producer Malcolm Cecil. “Angel Dust” peaked at No. 15 on the R&B charts in 1978.

In 1979, Scott-Heron played at the No Nukes concerts at Madison Square Garden. The concerts were organized by Musicians United for Safe Energy to protest the use of nuclear energy following the Three Mile Island accident. Scott-Heron’s song “We Almost Lost Detroit” was included in the No Nukes album of concert highlights. It alluded to a previous nuclear power plant accident and was also the title of a book by John G. Fuller. Scott-Heron was a frequent critic of President Ronald Reagan and his conservative policies.

Scott-Heron recorded and released four albums during the 1980s: 1980 and Real Eyes (1980), Reflections (1981) and Moving Target (1982). In February 1982, Ron Holloway joined the ensemble to play tenor saxophone. He toured extensively with Scott-Heron and contributed to his next album, Moving Target the same year. His tenor accompaniment is a prominent feature of the songs “Fast Lane” and “Black History/The World”. Holloway continued with Scott-Heron until the summer of 1989, when he left to join Dizzy Gillespie. Several years later, Scott-Heron would make cameo appearances on two of Ron Holloway’s CDs: Scorcher (1996) and Groove Update (1998), both on the Fantasy/Milestone label.

After Scott-Heron’s death, Malik Al Nasir told The Guardian’s Simon Hattenstone of the kindness that Scott-Heron had showed him throughout his adult life since meeting the poet back stage at a gig in Liverpool in 1984. The BBC World Service covered the story on their Outlook program with Matthew Bannister, which took the story global. It was subsequently covered in other media such as BBC Radio 4’s Saturday Live, where jazz musician Al Jarreau paid tribute to Gil, and was mentioned the U.S. edition of Rolling Stone and The Huffington Post. Malik & the O.G’s performed a tribute to Scott-Heron at the Liverpool International Music Festival in 2013 with jazz composer Orphy Robinson of The Jazz Warriors and Rod Youngs from Gil’s band The Amnesia Express. Another tribute was performed at St. Georges Hall in Liverpool on August 27, 2015, called “The Revolution will be Live!”, curated by Malik Al Nasir and Richard McGinnis for Yesternight Productions. The event featured Talib Kweli, Aswad, The Christians, Malik & the O.G’s, Sophia Ben-Yousef and Cleveland Watkiss as well as DJ 2Kind and poet, actor, and radio DJ Craig Charles. The tribute was the opening event for 2015 Liverpool International Music Festival.

Scott-Heron was dropped by Arista Records in 1985 and quit recording, though he continued to tour. The same year he helped compose and sang “Let Me See Your I.D.” on the Artists United Against Apartheid album Sun City, containing the famous line: “The first time I heard there was trouble in the Middle East, I thought they were talking about Pittsburgh.” The song compares racial tensions in the U.S. with those in apartheid-era South Africa, implying that the U.S. was not too far ahead in race relations. In 1993, he signed to TVT Records and released Spirits, an album that included the seminal track “‘Message to the Messengers”. The first track on the album criticized the rap artists of the day. Scott-Heron is known in many circles as “the Godfather of rap” and is widely considered to be one of the genre’s founding fathers. Given the political consciousness that lies at the foundation of his work, he can also be called a founder of political rap. Message to the Messengers was a plea for the new generation of rappers to speak for change rather than perpetuate the current social situation, and to be more articulate and artistic. Regarding hip hop music in the 1990s, he said in an interview:

Scott-Heron’s influence over hip hop is primarily exemplified by his definitive single “The Revolution Will Not Be Televised”, sentiments from which have been explored by various rappers, including Aesop Rock, Talib Kweli and Common. In addition to his vocal style, Scott-Heron’s indirect contributions to rap music extend to his and co-producer Jackson’s compositions, which have been sampled by various hip-hop artists. “We Almost Lost Detroit” was sampled by Brand Nubian member Grand Puba (“Keep On”), Native Tongues duo Black Star (“Brown Skin Lady”), and MF Doom (“Camphor”). Additionally, Scott-Heron’s 1980 song “A Legend in His Own Mind” was sampled on Mos Def’s “Mr. Nigga”, the opening lyrics from his 1978 recording “Angel Dust” were appropriated by rapper RBX on the 1996 song “Blunt Time” by Dr. Dre, and CeCe Peniston’s 2000 song “My Boo” samples Scott-Heron’s 1974 recording “The Bottle”.

In 2001, Scott-Heron was sentenced to one to three years imprisonment in a New York State prison for possession of cocaine. While out of jail in 2002, he appeared on the Blazing Arrow album by Blackalicious. He was released on parole in 2003, the year BBC TV broadcast the documentary Gil Scott-Heron: The Revolution Will Not Be Televised—Scott-Heron was arrested for possession of a crack pipe during the editing of the film in October 2003 and received a six-month prison sentence.

On July 5, 2006, Scott-Heron was sentenced to two to four years in a New York State prison for violating a plea deal on a drug-possession charge by leaving a drug rehabilitation center. He claimed that he left because the clinic refused to supply him with HIV medication. This story led to the presumption that the artist was HIV positive, subsequently confirmed in a 2008 interview. Originally sentenced to serve until July 13, 2009, he was paroled on May 23, 2007.

Malik Al Nasir dedicated a collection of poetry to Scott-Heron titled Ordinary Guy that contained a foreword by Jalal Mansur Nuriddin of The Last Poets. Scott-Heron recorded one of the poems in Nasir’s book entitled Black & Blue in 2006.

After his release, Scott-Heron began performing live again, starting with a show at SOB’s restaurant and nightclub in New York on September 13, 2007. On stage, he stated that he and his musicians were working on a new album and that he had resumed writing a book titled The Last Holiday, previously on long-term hiatus, about Stevie Wonder and his successful attempt to have the birthday of Martin Luther King Jr. declared a federally recognized holiday in the United States.

Scott-Heron died on the afternoon of May 27, 2011, at St. Luke’s Hospital, New York City, after becoming ill upon returning from a European trip. Scott-Heron had confirmed previous press speculation about his health, when he disclosed in a 2008 New York Magazine interview that he had been HIV-positive for several years, and that he had been previously hospitalized for pneumonia.

In April 2009, on BBC Radio 4, poet Lemn Sissay presented a half-hour documentary on Gil Scott-Heron entitled Pieces of a Man, having interviewed Gil Scott-Heron in New York a month earlier. Pieces of a Man was the first UK announcement from Scott-Heron of his forthcoming album and return to form. In November 2009, the BBC’s Newsnight interviewed Scott-Heron for a feature titled The Legendary Godfather of Rap Returns. In 2009, a new Gil Scott-Heron website, gilscottheron.net, was launched with a new track “Where Did the Night Go” made available as a free download from the site.

In 2010, Scott-Heron was booked to perform in Tel Aviv, Israel, but this attracted criticism from pro-Palestinian activists, who stated: “Your performance in Israel would be the equivalent to having performed in Sun City during South Africa’s apartheid era… We hope that you will not play apartheid Israel”. Scott-Heron responded by canceling the performance.

Scott-Heron released his album I’m New Here on independent label XL Recordings on February 9, 2010. Produced by XL label owner Richard Russell, I’m New Here was Scott-Heron’s first studio album in 16 years. The pair started recording the album in 2007, with the majority of the record being recorded over the 12 months leading up to the release date with engineer Lawson White at Clinton Studios in New York. I’m New Here is 28 minutes long with 15 tracks; however, casual asides and observations collected during recording sessions are included as interludes.

Scott-Heron admitted ambivalence regarding his association with rap, remarking in 2010 in an interview for the Daily Swarm: “I don’t know if I can take the blame for [rap music]”. As New York Times writer Sisario explained, he preferred the moniker of “bluesologist”. Referring to reviews of his last album and references to him as the “godfather of rap”, Scott-Heron said: “It’s something that’s aimed at the kids … I have kids, so I listen to it. But I would not say it’s aimed at me. I listen to the jazz station.” In 2013, Chattanooga rapper Isaiah Rashad recorded an unofficial mixtape called Pieces of a Kid, which was greatly influenced by Heron’s debut album Pieces of a Man.

The remix version of the album, We’re New Here, was released in 2011, featuring production by English musician Jamie xx, who reworked material from the original album. Like the original album, We’re New Here received critical acclaim.

Scott-Heron’s memorial service was held at Riverside Church in New York City on June 2, 2011, where Kanye West performed “Lost in the World” and “Who Will Survive in America”, two songs from West’s album My Beautiful Dark Twisted Fantasy. The studio album version of West’s “Who Will Survive in America” features a spoken-word excerpt by Scott-Heron. Scott-Heron is buried at Kensico Cemetery in Westchester County in New York.

In 2011, Rackley filed a suit against sister Gia Scott-Heron and her mother, Scott-Heron’s first wife, Brenda Sykes, as he believed they had unfairly attained US$250,000 of Scott-Heron’s money. The case was later settled for an undisclosed sum in early 2013; but the relationship between Rackley and Scott-Heron’s two adult daughters already had become strained in the months after Gil’s death. In her submission to the Surrogate’s Court, Kelly-Heron states that a DNA test completed by Rackley in 2011—using DNA from Scott-Heron’s brother—revealed that they “do not share a common male lineage”, while Rackley has refused to undertake another DNA test since that time. A hearing to address Kelly-Heron’s filing was scheduled for late August 2013, but by March 2016 further information on the matter was not publicly available. Rackley still serves as court-appointed administrator for the estate, and donated material to the Smithsonian’s new National Museum of African American History and Culture for Scott-Heron to be included among the exhibits and displays when the museum opened in September 2016. In December 2018, the Surrogate Court ruled that Rumal Rackley and his half sisters are all legal heirs.

Following Scott-Heron’s funeral in 2011, a tribute from publisher, record company owner, poet, and music producer Malik Al Nasir was published on The Guardian’s website, titled “Gil Scott-Heron saved my life”.

Scott-Heron was honored posthumously in 2012 by the National Academy of Recording Arts and Sciences with a Grammy Lifetime Achievement Award. Charlotte Fox, member of the Washington, DC NARAS and president of Genesis Poets Music, nominated Scott-Heron for the award, while the letter of support came from Grammy award winner and Grammy Hall of Fame inductee Bill Withers.

Scott-Heron’s memoir, The Last Holiday, was published in January 2012. In her review for the Los Angeles Times, professor of English and journalism Lynell George wrote:

At the time of Scott-Heron’s death, a will could not be found to determine the future of his estate. Additionally, Raquiyah Kelly-Heron filed papers in Manhattan, New York’s Surrogate’s Court in August 2013, claiming that Rumal Rackley is not Scott-Heron’s son and should therefore be omitted from matters concerning the musician’s estate. According to the Daily News website, Rackley, Kelly-Heron and two other sisters have been seeking a resolution to the issue of the management of Scott-Heron’s estate, as Rackley stated in court papers that Scott-Heron prepared him to be the eventual administrator of the estate. Scott-Heron’s 1994 album Spirits was dedicated to “my son Rumal and my daughters Nia and Gia”, and in court papers Rackley added that Scott-Heron introduced me [Rackley] from the stage as his son.”

In April 2014, XL Recordings announced a third album from the I’m New Here sessions, titled Nothing New. The album consists of stripped-down piano and vocal recordings and was released in conjunction with Record Store Day on April 19, 2014.

According to the Daily News website, Kelly-Heron and two other sisters have been seeking a resolution to the issue of the management of Scott-Heron’s estate. The case was decided in December 2018 with a ruling issued in May 2019.

In the 2018 film First Man, Scott-Heron is a minor character and is played by soul singer Leon Bridges.

He is one of eight significant people shown in mosaic at the 167th Street renovated subway station on the Grand Concourse in the Bronx that reopened in 2019.